ive try any single way to make multiple box of lightbox in one page,ive replace each possible class and variable, but the image on lighbox 1,and 2 doesnt appear,or vice versa.ive try another way to solve this by reading any program on internet, but ive to try more to make this project cause this project has taken 3 days.

 //  for lighbox1
    function openModal() {
      document.getElementById("myModal1").style.display = "block";
    }
    
    function closeModal() {
      document.getElementById("myModal1").style.display = "none";
    }
// -------------------------
    var slideIndex1 = 1;
    showSlides(slideIndex1);
    
    function plusSlides(n) {
      showSlides(slideIndex1 += n);
    }
    
    function currentSlide(n) {
      showSlides(slideIndex1 = n);
    }
 // lighbox1
 function showSlides(n) {
      var i;
      var slides1 = document.getElementsByClassName("mySlides1");
      var dots1 = document.getElementsByClassName("demo1");
      var captionText1 = document.getElementById("caption1");
      
// lighbox 1
      if (n > slides1.length) {slideIndex1 = 1}
      if (n < 1) {slideIndex1 = slides1.length}
      for (i = 0; i < slides1.length; i++) {
          slides1[i].style.display = "none";
      }
      for (i = 0; i < dots1.length; i++) {
          dots1[i].className = dots1[i].className.replace(" active", "");
      }
      slides1[slideIndex1-1].style.display = "block";
      dots1[slideIndex1-1].className += " active";
      captionText1.innerHTML = dots1[slideIndex1-1].alt;
    }

    // ---------------------------------------
   //  =======================================
    // for lighbox2
    function openModal() {
      document.getElementById("myModal2").style.display = "block";
    }
    
    function closeModal() {
      document.getElementById("myModal2").style.display = "none";
    }
   //  ---------------------
    var slideIndex2 = 1;
    showSlides(slideIndex2);
    
    function plusSlides(o) {
      showSlides(slideIndex2 += o);
    }
    
    function currentSlide(o) {
      showSlides(slideIndex2 = o);
    }
    // lightbox2
    function showSlides(o){
      var j;
      var mySlides2 = document.getElementsByClassName("mySlides2");
      var dots2 = document.getElementsByClassName("demo2");
      var captionText2 = document.getElementById("caption2");

       // lighbox 2
       if (o > slides2.length) {slideIndex2 = 1}
      if (o < 1) {slideIndex2 = slides2.length}
      for (j = 0; j < slides2.length; j++) {
          slides2[j].style.display = "none";
      }
      for (j = 0; j < dots2.length; j++) {
          dots2[j].className = dots2[j].className.replace(" active", "");
      }
      slides2[slideIndex2-1].style.display = "block";
      dots2[slideIndex2-1].className += " active";
      captionText2.innerHTML = dots2[slideIndex2-1].alt;
    
    }
    // ---------------------------------------
   //  =======================================
    // for lighbox3
    function openModal() {
      document.getElementById("myModal3").style.display = "block";
    }
    
    function closeModal() {
      document.getElementById("myModal3").style.display = "none";
    }
   //  --------------------
    var slideIndex3 = 1;
    showSlides(slideIndex3);
    
    function plusSlides(p) {
      showSlides(slideIndex3 += p);
    }
    
    function currentSlide(p) {
      showSlides(slideIndex3 = p);
    }
     // lighbox3
     function showSlides(p){
      var k;
      var slides3 = document.getElementsByClassName("mySlides3");
      var dots3 = document.getElementsByClassName("demo3");
      var captionText3 = document.getElementById("caption3");

      // lighbox 3
      if (p > slides3.length) {slideIndex3 = 1}
      if (p < 1) {slideIndex3 = slides3.length}
      for (k = 0; k < slides3.length; k++) {
          slides3[k].style.display = "none";
      }
      for (k = 0; k < dots3.length; k++) {
          dots3[k].className = dots3[k].className.replace(" active", "");
      }
      slides3[slideIndex3-1].style.display = "block";
      dots3[slideIndex3-1].className += " active";
      captionText3.innerHTML = dots3[slideIndex3-1].alt;
    }
    // ---------------------------------------
body {
  font-family: Verdana, sans-serif;
  margin: 0;
}

* {
  box-sizing: border-box;
}

.row > .column {
  padding: 0 8px;
}

.row:after {
  content: "";
  display: table;
  clear: both;
}

.column {
  float: left;
  width: 25%;
}

/* The Modal (background) */
.modal {
  display: none;
  position: fixed;
  z-index: 1;
  padding-top: 100px;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  overflow: auto;
  background-color: black;
}

/* Modal Content */
.modal-content {
  position: relative;
  background-color: #fefefe;
  margin: auto;
  padding: 0;
  width: 90%;
  max-width: 1200px;
}

/* The Close Button */
.close {
  color: white;
  position: absolute;
  top: 10px;
  right: 25px;
  font-size: 35px;
  font-weight: bold;
}

.close:hover,
.close:focus {
  color: #999;
  text-decoration: none;
  cursor: pointer;
}

.mySlides1.mySlides2.mySlides3 {
  display: none;
}

.cursor {
  cursor: pointer;
}

/* Next & previous buttons */
.prev,
.next {
  cursor: pointer;
  position: absolute;
  top: 50%;
  width: auto;
  padding: 16px;
  margin-top: -50px;
  color: white;
  font-weight: bold;
  font-size: 20px;
  transition: 0.6s ease;
  border-radius: 0 3px 3px 0;
  user-select: none;
  -webkit-user-select: none;
}

/* Position the "next button" to the right */
.next {
  right: 0;
  border-radius: 3px 0 0 3px;
}

/* On hover, add a black background color with a little bit see-through */
.prev:hover,
.next:hover {
  background-color: rgba(0, 0, 0, 0.8);
}

/* Number text (1/3 etc) */
.numbertext {
  color: #f2f2f2;
  font-size: 12px;
  padding: 8px 12px;
  position: absolute;
  top: 0;
}

img {
  margin-bottom: -4px;
}

.caption-container {
  text-align: center;
  background-color: rgb(10, 10, 10);
  padding: 2px 16px;
  color: white;
}

.demo {
  opacity: 0.6;
}

.active,
.demo:hover {
  opacity: 1;
}

img.hover-shadow {
  transition: 0.3s;
}

.hover-shadow:hover {
  box-shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.2), 0 6px 20px 0 rgba(0, 0, 0, 0.19);
}
<h2 style="text-align:center">Lightbox1</h2>
<!-- this for lightbox 1 -->
<div class="row">
  <div class="column">
    <img src="https://source.unsplash.com/j7xx4uDVoCo/1600x900" style="width:100%" onclick="openModal();currentSlide(1)" class="hover-shadow cursor">
  </div>
  <div class="column">
    <img src="https://source.unsplash.com/ZS67i1HLllo/1600x900" style="width:100%" onclick="openModal();currentSlide(2)" class="hover-shadow cursor">
  </div>
  <div class="column">
    <img src="https://source.unsplash.com/YiX1jsdbWhY/1600x900" style="width:100%" onclick="openModal();currentSlide(3)" class="hover-shadow cursor">
  </div>
  <div class="column">
    <img src="https://source.unsplash.com/jafl5owXXVc/1600x900" style="width:100%" onclick="openModal();currentSlide(4)" class="hover-shadow cursor">
  </div>
</div>

<div id="myModal1" class="modal">
  <span class="close cursor" onclick="closeModal()">&times;</span>
  <div class="modal-content">

    <div class="mySlides1">
      <div class="numbertext">1 / 4</div>
      <img src="https://source.unsplash.com/j7xx4uDVoCo/1600x900" style="width:100%">
    </div>

    <div class="mySlides1">
      <div class="numbertext">2 / 4</div>
      <img src="https://source.unsplash.com/ZS67i1HLllo/1600x900" style="width:100%">
    </div>

    <div class="mySlides1">
      <div class="numbertext">3 / 4</div>
      <img src="https://source.unsplash.com/YiX1jsdbWhY/1600x900" style="width:100%">
    </div>
    
    <div class="mySlides1">
      <div class="numbertext">4 / 4</div>
      <img src="https://source.unsplash.com/jafl5owXXVc/1600x900" style="width:100%">
    </div>
    
    <a class="prev" onclick="plusSlides(-1)">&#10094;</a>
    <a class="next" onclick="plusSlides(1)">&#10095;</a>

    <div class="caption-container">
      <p id="caption"></p>
    </div>


    <div class="column">
      <img class="demo cursor" src="https://source.unsplash.com/j7xx4uDVoCo/1600x900" style="width:100%" onclick="currentSlide(1)" alt="Nature and sunrise">
    </div>
    <div class="column">
      <img class="demo cursor" src="https://source.unsplash.com/ZS67i1HLllo/1600x900" style="width:100%" onclick="currentSlide(2)" alt="Snow">
    </div>
    <div class="column">
      <img class="demo cursor" src="https://source.unsplash.com/YiX1jsdbWhY/1600x900" style="width:100%" onclick="currentSlide(3)" alt="Mountains and fjords">
    </div>
    <div class="column">
      <img class="demo cursor" src="https://source.unsplash.com/jafl5owXXVc/1600x900" style="width:100%" onclick="currentSlide(4)" alt="Northern Lights">
    </div>
  </div>
</div>
<!-- end lightbox1 -->
<br>
<br>
<br>

<!-- this for lighbox2 -->
<h2 style="text-align:center">Lightbox2</h2>
<div class="row">
   <div class="column">
     <img src="https://source.unsplash.com/0qvBNep1Y04/1600x900" style="width:100%" onclick="openModal();currentSlide(1)" class="hover-shadow cursor">
   </div>
   <div class="column">
     <img src="https://source.unsplash.com/BfrQnKBulYQ/1600x900" style="width:100%" onclick="openModal();currentSlide(2)" class="hover-shadow cursor">
   </div>
   <div class="column">
     <img src="https://source.unsplash.com/9wTPJmiXk2U/1600x900" style="width:100%" onclick="openModal();currentSlide(3)" class="hover-shadow cursor">
   </div>
   <div class="column">
     <img src="https://source.unsplash.com/O2MdroNurVw/1600x900" style="width:100%" onclick="openModal();currentSlide(4)" class="hover-shadow cursor">
   </div>
 </div>

 <div id="myModal2" class="modal">
   <span class="close cursor" onclick="closeModal()">&times;</span>
   <div class="modal-content">
 
     <div class="mySlides2">
       <div class="numbertext">1 / 4</div>
       <img src="https://source.unsplash.com/0qvBNep1Y04/1600x900" style="width:100%">
     </div>
 
     <div class="mySlides2">
       <div class="numbertext">2 / 4</div>
       <img src="https://source.unsplash.com/BfrQnKBulYQ/1600x900" style="width:100%">
     </div>
 
     <div class="mySlides2">
       <div class="numbertext">3 / 4</div>
       <img src="https://source.unsplash.com/9wTPJmiXk2U/1600x900" style="width:100%">
     </div>
     
     <div class="mySlides2">
       <div class="numbertext">4 / 4</div>
       <img src="https://source.unsplash.com/O2MdroNurVw/1600x900" style="width:100%">
     </div>
     
     <a class="prev" onclick="plusSlides(-1)">&#10094;</a>
     <a class="next" onclick="plusSlides(1)">&#10095;</a>
 
     <div class="caption-container">
       <p id="caption1"></p>
     </div>
 
 
     <div class="column">
       <img class="demo1 cursor" src="https://source.unsplash.com/0qvBNep1Y04/1600x900" style="width:100%" onclick="currentSlide(1)" alt="Nature and sunrise">
     </div>
     <div class="column">
       <img class="demo1 cursor" src="https://source.unsplash.com/BfrQnKBulYQ/1600x900" style="width:100%" onclick="currentSlide(2)" alt="Snow">
     </div>
     <div class="column">
       <img class="demo1 cursor" src="https://source.unsplash.com/9wTPJmiXk2U/1600x900" style="width:100%" onclick="currentSlide(3)" alt="Mountains and fjords">
     </div>
     <div class="column">
       <img class="demo1 cursor" src="https://source.unsplash.com/O2MdroNurVw/1600x900" style="width:100%" onclick="currentSlide(4)" alt="Northern Lights">
     </div>
   </div>
 </div>
 <!-- end ligtbox2 -->
 <br>
 <br>
 <br>
 <!-- this ligtbox3 -->
 <h2 style="text-align:center">Lightbox3</h2>
 <div class="row">
   <div class="column">
     <img src="https://source.unsplash.com/gnyA8vd3Otc/1600x900" style="width:100%" onclick="openModal();currentSlide(1)" class="hover-shadow cursor">
   </div>
   <div class="column">
     <img src="https://source.unsplash.com/g5jpH62pwes/1600x900" style="width:100%" onclick="openModal();currentSlide(2)" class="hover-shadow cursor">
   </div>
   <div class="column">
     <img src="https://source.unsplash.com/JpF58ANavoc/1600x900" style="width:100%" onclick="openModal();currentSlide(3)" class="hover-shadow cursor">
   </div>
   <div class="column">
     <img src="https://source.unsplash.com/mZRCMPbJSPc/1600x900" style="width:100%" onclick="openModal();currentSlide(4)" class="hover-shadow cursor">
   </div>
 </div>
 
 <div id="myModal3" class="modal">
   <span class="close cursor" onclick="closeModal()">&times;</span>
   <div class="modal-content">
 
     <div class="mySlides3">
       <div class="numbertext">1 / 4</div>
       <img src="https://source.unsplash.com/gnyA8vd3Otc/1600x900" style="width:100%">
     </div>
 
     <div class="mySlides3">
       <div class="numbertext">2 / 4</div>
       <img src="https://source.unsplash.com/g5jpH62pwes/1600x900" style="width:100%">
     </div>
 
     <div class="mySlides3">
       <div class="numbertext">3 / 4</div>
       <img src="https://source.unsplash.com/JpF58ANavoc/1600x900" style="width:100%">
     </div>
     
     <div class="mySlides3">
       <div class="numbertext">4 / 4</div>
       <img src="https://source.unsplash.com/mZRCMPbJSPc/1600x900" style="width:100%">
     </div>
     
     <a class="prev" onclick="plusSlides(-1)">&#10094;</a>
     <a class="next" onclick="plusSlides(1)">&#10095;</a>
 
     <div class="caption-container">
       <p id="caption2"></p>
     </div>
 
 
     <div class="column">
       <img class="demo2 cursor" src="https://source.unsplash.com/gnyA8vd3Otc/1600x900" style="width:100%" onclick="currentSlide(1)" alt="Nature and sunrise">
     </div>
     <div class="column">
       <img class="demo2 cursor" src="https://source.unsplash.com/g5jpH62pwes/1600x900" style="width:100%" onclick="currentSlide(2)" alt="Snow">
     </div>
     <div class="column">
       <img class="demo2 cursor" src="https://source.unsplash.com/JpF58ANavoc/1600x900" style="width:100%" onclick="currentSlide(3)" alt="Mountains and fjords">
     </div>
     <div class="column">
       <img class="demo2 cursor" src="https://source.unsplash.com/mZRCMPbJSPc/1600x900" style="width:100%" onclick="currentSlide(4)" alt="Northern Lights">
     </div>
   </div>
 </div>
<!-- end lightbox3 -->