How to remove gmail account and reformat

@akiraubpon you can only do that if you have the original password. If you do not have that, you can not remove the email address. All part of the FRP security feature to prevent unauthorized use after a factory reset. It does require the Google account credentials that were used when this phone was originally setup.

If you do not have that access, you officially can't get into this phone for a fresh install.

Firmware, software, flashing and missing (forgotten) passwords, are really not what we deal with on here. We are more of the hardware repair kind of group. For your "issue" I suggest you check those forums that deal with that. Do a search for FRP bypass