You need to code that. U will need :
-
https://www.wix.com/corvid/reference/$w.Button.html#disable
https://www.wix.com/corvid/reference/$w.Button.html#enable
for the button to disable enable after conditions (payment)
(disable when page is loaded and then if payment is correct enable button) -
paypal button with HTML embed or
after a purchase in wix store at the “thank you” page redirecting him to the previous page with button being,now, enabled
https://www.wix.com/corvid/reference/wix-location.html#to