linking “add to cart” to a certain page

I am trying to link the “add to cart” button so when you click it it takes you to the cart page and shows the product in the cart.

From here: https://adubsdesign.com/blog/?page_id=14&category=3&product_id=3
clicking the button leaves you at the same page.
I think this is an easy fix but I don’t know where to edit the link for that button.