Suppose you have a button: Checkout on Announcement Bar, and a product on your site. You want: When users click on this Checkout button >> It will add the product to the cart and open the checkout page.

#1. First, you need to follow this code to add a button to the Announcement Bar

#2. Next, enable Express Checkout

#3. Add a Product Block (you can add it to Site Footer)

#4. Use this code to Code Injection – Footer

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.0/jquery.min.js"></script>
<script>
$(document).on('click', '#announcement-bar-text-inner-id p a', function(event) { 
    event.preventDefault(); 
    $('div.sqs-add-to-cart-button').click(); 
});
</script>