But first I DISAGREE that a stock install of Windows today will result in " if one gets into router or wifi they can get into the PC with it's Win PW." A stock install of Windows does not allow this today.
As to survive a reset, that means you have to do a clean install. How to Clean Install Windows 10 is all over the web so I won't duplicate this here.
If you feel it's time to change router name and password, do that now.
If you feel it's time to clean install Windows, do that now.
If you feel your life is in danger, call the police now.