how to add javascript to html pagination code example

Example: pagination html css how to working

<nav aria-label="...">
  <ul class="pagination">
    <li class="page-item disabled">
      <a class="page-link" href="#" tabindex="-1">Previous</a>
    </li>
    <li class="page-item"><a class="page-link" href="#">1</a></li>
    <li class="page-item active">
      <a class="page-link" href="#">2 <span class="sr-only">(current)</span></a>
    </li>
    <li class="page-item"><a class="page-link" href="#">3</a></li>
    <li class="page-item">
      <a class="page-link" href="#">Next</a>
    </li>
  </ul>
</nav>