Here is the tutorial which explains how to create the Confirmation box in Javascript with Yes No options.

Create onclick event in html coding:

<a onClick="return verifydelete()" href="viewcustomer.php" class="templatemo-edit-btn">Delete</a>

Javascript coding:

<script type="application/javascript">
function verifydelete()
{
	if(confirm("Are you sure want to delete this record...???") == true)
	{
		return true;
	}
	else
	{
		return false;
	}
}
</script>