Back up your data
Sign out of iCloud
Sign out of Messages
Sign out of Music, TV, and other Apple services
Restart your MacBook Pro
Enter macOS Recovery
On Apple silicon, press and hold the power button until startup options appear, then select Options and click Continue
On Intel, restart and immediately hold Command + R
Open Disk Utility
Select Macintosh HD or your startup disk
Click Erase
Choose APFS or Mac OS Extended if prompted
Confirm the erase
Quit Disk Utility
Select Reinstall macOS
Follow the on-screen instructions
Set up the MacBook Pro or shut it down for the next user