Properly reset android 7 settings?

Question

Android

I saw that if with android 5-9 I forgot the password from the Google account in the phone, then the firmware saves ...
And if you don’t register with Google at all? And not with google play software, but with w3bsit3-dns.com? Is it easier to reset to factory settings?
How do tnhnari pros handle android 7 phones in general? Do they keep the downloaded firmware on the PC? Or is there another backup ...
With a PC, it's easier, after all! Backups ...
What else do they get on android 7?
If there is no antivirus? Or locked your phone and forgot the key?

Answer 1

We go into service mode and return the smartphone to the factory firmware