Booting into Windows partition prompts for firmware password I installed Windows 10 via Boot Camp couple of months ago and it worked normally. Today I tried to boot into Windows, but a password form pops up (firmware protection form). Booting into macOS without holding option key works OK.

I have tried entering the passwords for an admin account, my Apple ID, and iCloud, as well as booting into local and network recovery modes. Nothing worked.

I don't have "Find My Mac" installed or a recovery partition.

Where I can find this password or bypass it?
This is normal, and is likely because you enabled a Firmware Password while under Recovery Mode. Having a firmware password prevents your computer from booting from other boot partitions besides your main MacOS partition without your permission.

For more reference, view the relevant Apple Support page here.