API questionAnswered

So I am having issues with the API again, I've never successfully got this working and I gave up a few months ago but it's really hurting my sales not having this be a thing.

I'm using shoppy.gg to sell my products but I need to setup that when a customer purchases a license, it generates the license and sends it back to shoppy. I also need it to setup the membership time to 30 days from purchase time. That being said I've never been able to do it and given up on it in the past.

Shoppy products allow you to add webhooks and a callback url. I have 0 clue how to do this.

That is what I was trying. Can someone guide me on the right path please?