How to manually spoof package in supported custom roms ?

[lucius100]

First I want to ask about cust partition.
What is cust partition ? Because I accidentally wiped it when flashing custom rom, but I don't have any issues for now, just curious if it will cause any problems in the future ?


Also the main question is how to manually spoof the package ?
From what I saw so far, only app that designed to request spoofing permissions are allowed, such as microg.
If I want to spoofing certain app, how to do it ?
I read somewhere said we can spoof it via termux ? but how ?
Or we need to modify the apk to add request spoofing permission manifest ? How ?

Thanks