To set an image as the marker in list-item, use the listStyleImage property in JavaScript.
Example
You can try to run the following code to set an image as the list-item marker with JavaScript −
<!DOCTYPE html>
<html>
<body>
<ol id="myID">
<li>One</li>
<li>Two</li>
</ol>
<button type="button" onclick="display()">Update list image</button>
<script>
function display() {
document.getElementById("myID").style.listStyleImage = "url('https://tutorialspoint.com/css/images/bullet.gif')";
}
</script>
</body>
</html>