Firebase config file error - I want to fix firebase error, please help

Where and how is the package name created? Thank you very much for what you did for me.

I found where the package name is and my application became an apk thanks to all your help. Thank you very much for everything.

I get the Firebase Auth doesn’t work in the Companion error, what should I do?

I think you could have avoided the whole problem if you had followed a guide on how to integrate Auth.
Authentication does not work on the companion.

Hello. Thank you very much for your reply. I offer my respects. The problem is that I set up the authentication correctly and I was able to get an apk for my application and I installed my application-apk on my phone, but when I try to register to create an account for testing purposes, it does not create an account and go to the login page. This is the problem, can you help me?