How to recover by pressing f8 when starting the machine?

This is only useful when installing the bootloader. You cannot restore the system without installing it.

For example, installing a dwarf studio or one-click restore can only be said, and you should make a backup of ghost in advance, otherwise it will be empty.

In addition, you can reinstall or restore the system by booting from the CD. Just go shopping and buy a CD or burn a CD yourself.