Lock out by an EFI password or firmware password

I got a efi lock while trying to access my Mac OS on my Apple Mac air 13

i do have windows and iOS install in the device ... I have been using windows for years now the laptop keep asking me to use a password I never imputed at the first place before I can use back any of the Operating system install on the device... it has a lock key on the screen.

please how can I go back to using my windows operating system?