I try to answer your questions:
1.Factory reset will NOT reset the BIOS too, only your OS.You can only reset the BIOS by clearing the CMOS memory (there it stores the settings) or manually loading default settings when you are in the BIOS.
2.If you reset Windows, it will NOT replace the manufacturer drivers the laptop came with.
3.Windows does have a built-in factory reset function that will delete your personal data and keep only the OS. You can find in Settings > Update & Recovery > Recovery tab