android project organisation

Hi,
I am Shubham & I'm working in a mobile app development company & doing a project with firestore...so the app I'm working on have model classes.
I need to import data to preload firestore (reference data, test data and so on) so I used admin SDK but the preload code needs models classes too.

My question :

How organize my project :

1) Should I put admin classes (that do import with a main function) in the app module and tell gradle to not put it in the app when building ?

2) Should I put my admin classes in another module (android library, ..) but in this case where should be my models classes ? in the app module, in the library module, .. ?

Please advice
Ty for your help...