Back up any data you want to keep
Shut down the MacBook Pro
Turn it on and immediately hold Command + R until macOS Recovery appears
If Command + R does not work on Apple silicon, press and hold the power button until startup options appear, then select Options and click Continue
In Recovery, open Disk Utility
Select the internal drive or Macintosh HD
Click Erase
Choose APFS or Mac OS Extended if required
Confirm the erase
Quit Disk Utility
Select Reinstall macOS from the Recovery menu
Follow the on-screen prompts to reinstall macOS
If Activation Lock appears, enter the Apple ID and password linked to the Mac
If you cannot bypass Activation Lock, contact Apple Support with proof of ownership