How can I create a single 'download' button for purchases in my store?

Hello everyone. Please tell me, I need to make it possible to purchase in my store through one button (I attached an example photo) But I don’t understand how to do it. I only have two buttons “buy” and “add to cart” available, but I need one button that says “download” and that after clicking on this button, the person is transferred to the cart. I would be very grateful for a feedback:)

@Slapik

This is possible but this code customization works.

Thanks!

Thanks for the answer, but I still don’t understand. If it’s not difficult for you, maybe we could call on zoom so that you can show me how to do it? Or can you recommend some video where there is a solution of my question? Thank you in advance