I just hesitate to suggest alternatives to Windows I have had so many people who are either afraid of a change outside the MS world or when they start talking about their intended use and what they "need" to do or keep it often lands me looking to getting them up on a MS system again. I know that these alternatives can be great for people but I have a habit now of keeping people as close to what they had as I can. I am not sure how best to clarify at the moment but it sounds like a MS Account as otherwise they wouldn't be enforcing password requirements which means cracking it is tougher and given the system probably not worth it. I would see about getting a Win10 boot media for that laptop and do a clean install from it this will let you setup a new account and password. You are not required to make a MS Account but getting away from that is becoming trickier and more difficult. For password issues like trouble keeping up with them some people use a "password locker" basically a single file/program with a password or lock of some kind that inside is all your IDs and Passwords that you have stored there. It has its risks but for many people it is the best compromise to the "Don't write down your PW rule"