How to confirm orders with Printful via DIY coding?

Question:
I’m making a store from scratch and need to know how to code confirmations towards Printful as to what the customer wants.

Product:
Wix Studio, Printful, Velo

What are you trying to achieve:
So that transactions are dealt with successfully for both ends.

What have you already tried:
Looking at Printful’s blogs and Wix’s blogs and googling.

Additional information:
Any documentation or other resources you can point me to would be great ^^"

Are you creating your own store, as in creating your own frontend and using Wix Ecomm/Stores APIs or fully creating your own infra around stores?

Perhaps the existing integrations would help if you’re not creating your own backend - Wix Stores: Connecting to Printful | Help Center | Wix.com

I’m trying to make the front-end from scratch and then tell Printful and whoever else necessary in the back-end what order has been made. I just need that nugget of a button that does the transaction and legitimatizes the order.