Reset used iMac - no password or id for machine
Got a very used iMac from a friend (os X Yosemite). I just need it to demo something so it's fine. I cannot get into the thing. The PW I was given does not work. I am not a Mac person, so the explanations I've been following are being followed literally.
I've managed to get to reload the OS, but when I try to do that, it wants an Apple ID. Okay, so I created one. Nope - no progress.
Not sure what else to do. would appreciate some helpful hints.
iMac (24-inch, M1, 2021, 2 ports)