Convert Appsheet inventory app to Xcode

I have an existing Appsheet app I developed that uses Google Sheets backend for the database. The app is an inventory management app to manage furniture inventory items. I would like to convert the app to a native Xcode app that supports database management (mySQL or Firebase) and user registration and authentication. I have a beta version of the app that's available via TestFlight (Appsheet created iOS native app) that I can provide as an example to use for reviewing the various screens/views, menus, functionality, etc.