I want my customers to click the add to cart button and upon clicking this button I want them to go directly to the checkout page instead of the "view your cart" page. How would hiding the Add to cart help achieve this? Please let me know if I misunderstood you.
you have to enable buy-it-now button.
Customers use this button to checkout directly.
Modify add-to-cart button is possible but it destroys the purpose of the button.