How can I add the price to my add to cart button on focal theme?
Yes, this is possible in the Focal theme. We can dynamically display the selected variant price inside the Add to Cart button, and it will automatically update when the customer changes variants. This requires a small theme code customization and works with regular prices and sales.
This requires a small script to be added in your theme files. Here is a Youtube Video showing a step by step process. They are using Dawn theme for example but it will allow you to see what is needed. Since you are using Focal theme, it will need to have different names for the button and price. https://youtu.be/XorhlJIBZFk?si=6ZUNCLT48Y9H8fjm
Did you ask the Shopify Sidekick tool?
No that does not work. I has to work just like the normal price. No disappearing or glitching when changing variants