how can format macbook air

[anvershsa]

i can`t format my mac

 

[Andrea Mathew]

Hi,
Hope you are looking for re-installation of the OS.
Open OS X Utilities. There are 2 option that you can choose. Either select Reinstall OS X option for a complete re-installation or select Restore from a Time Machine Backup which allows you to restore your machine to the latest Time Machine backup, if you have one.