1. macOS Install

See https://support.apple.com/en-us/102662 to download the installer.

See https://support.apple.com/en-us/101578 to create a bootable USB drive.

1.1. Create a bootable installer

Insert a removable disk, then create the bootable installer:

$ sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --downloadassets --volume /Volumes/XxxxVolume

XxxxVolume is the name of the volume.

1.2. Install

Turn on the computer and hold the Option/Alt key to see the boot menu.