Copy And Paste Below Code
<div style="
position: fixed;
bottom: 10px;
right: 0;
width: 50px;
height: 50px;
margin: 15px;" class="whatsapp-bottom">
<a href="https://wa.me/+441234567823">
<img height="100" width="100" src="https://yourwebsite.net/wp-content/uploads/2023/10/whatsapp.png">
</a>
</div>