Sales Channel for Shopify

I built an app (I hired people to build the app) to connect with Shopify. We were told that that we are a sales channel and not an app. The app is built and I am looking to see if it is possible to change it to a sales channel. I have been told it is next to impossible. Any help is appreciated.

Did you have any luck with this. I’d love to know your experience connecting as a sale channel to Shopify