Hello @norvin_mago
I was able to do that with both of these sites Toplace.com & Ciro3D.com by utilizing Foxy.io as a shopping cart integrated with Webflow. You can see more documentation on it Here.
Foxy.io has step by step integration documentation on how to integrate advanced analytics.
However setting up simple Ecommerce tracking is as simple as checking a switch in the admin settings of your foxy.io back-end, once you place a few lines of code on your website and have foxy set-up. This set-up will track transactions, product category, etc…
By using Foxy.io integrated into Webflow you can use Paypal directly set-up through @foxy to accept payments. When setting up a check-out funnel inside of Google Analytics you can use Paypal
check out links to track when a user finishes a conversion outside of your site inside of the Paypal portal.
I suggest setting up a Paypal sandbox account to test your funnel.
You can also use a site like HotJar.com to set-up a funnel, heat maps, polls, and more for your site.
Let me know if you need any more help 
- Scott