PayPal Integration - Shopping cart will not enable

Hi there,
I am trying integrate PayPal into my site but I get a ‘Checkout is disabled on this site’ message.
When I enable checkout and republish, I get no buttons at all at the bottom of my shopping cart.
After watching dozens of videos and reading countless webpages about how easy the process is, I still have a non working shopping cart and no idea how to troubleshoot it.
I am hoping someone can help as the Support email has been unresponsive.

Here is my site Read-Only: [LINK][Webflow - NittyGrittyInc]