My MBP is stuck on Firmware screen won’t launch

If you don't know the password or the password is not working, then you will need to take the laptop to an Apple Store or an Apple Authorized Service Provider to have them remove the firmware lock. You will need to provide valid proof of purchase which usually requires a receipt with your name and the system serial number. You will need to provide proof of your identity as well. It would be best to contact Apple or the AASP first to confirm exactly what paperwork you will need to provide them as proof of ownership.