How can I reset my MacBook after I have backed it up?
How can I reset my MacBook Air after I have backed it up?
MacBook Air (2020 or later)
That would depend on your Mac's chip and macOS version
For intel-based Macs
Use Disk Utility to erase an Intel-based Mac - Apple Support
For Apple Silicon Macs
Use Disk Utility to erase a Mac with Apple silicon - Apple Support
For Macs with macOS Monterey, they have this option
Erase all content and settings on Mac - Apple Support
Hope that helps! Best of luck!