!DOCTYPE html>
<html>
<title>CSS</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://www.w3schools.com/w3css/4/w3.css">
<body>

<div class="w3-content w3-display-container">
  <img class="class_name" src="image_name" style="width:100%">
  <button class="w3-button w3-black w3-display-left" onclick="funtion_name(-1)">&#10094;</button>
  <button class="w3-button w3-black w3-display-right" onclick="funtion_name(1)">&#10095;</button>
</div>

<script>
var slideIndex = 1;
showDivs(slideIndex);

function funtion_name(n) {
  showDivs(slideIndex += n);
}

function showDivs(n) {
  var i;
  var x = document.getElementsByClassName("silder");
  if (n > x.length) {slideIndex = 1}    
  if (n < 1) {slideIndex = x.length}
  for (i = 0; i < x.length; i++) {
     x[i].style.display = "none";  
  }
  x[slideIndex-1].style.display = "block";  
}
</script>

</body>
</html>