How to redirect "Checkout Button" to a form

I'm new to Squarespace and I'm trying to redirect the checkout button in cart to redirect to a "request a quote" form using Javascript. I need it to record the items in cart for the Quote. I've been just trying to change the button redirect, but it only redirects to my form for half of a second and then overwrites with the default checkout.

2 hours ago, gracegiebel said:

I'm trying to redirect the checkout button in cart to redirect to a "request a quote" form

If you'd like a supported solution that's already been built for this purpose, please take a look at the Wishlist paid plugin.