My keyboard has defective letter
I’m not sure what’s going on but my keyboard letter “m” does not work, it beeps when I press it. I need that letter because it was part of my password to get on my desktop iMac. I bought a new keyboard but I need to access my system folder which I can’t do if I can’t get into my iMac desktop. Help, please.
iMac 21.5″ 4K, macOS 13.7