how to create info and help alert div in html code example

Example 1: how to make an alert in html

<script>
  alert('this is an alert');
</script>

Example 2: alert bootstrap

<div class="alert alert-warning alert-dismissible fade show" role="alert">
  <strong>Holy guacamole!</strong> You should check in on some of those fields below.
  <button type="button" class="close" data-dismiss="alert" aria-label="Close">
    <span aria-hidden="true">×</span>
  </button>
</div>