How can I create one click upsells while using 2Checkout?

I thought using Membership 2 Pro but I am not sure how to integrate with 2CO in order to have an upsell right after first sale.

Should I try using Marketplace, since it has Add to Cart button?

Idea is to have a more seamless experience:

when a user buys a guitar course, I would immediately offer him something as an upsell. The only thing that I am trying to avoid is users having to fill in their cc details twice.

Any ideas?

Pls help :slight_smile: