All you need to install any version of Raspberry Pi OS is the Imager tool, an SD card and reader, and around ten minutes.

Updating the EEPROM ensures that the Raspberry Pi 5 is equipped to handle the latest network-based OS installation commands.

Install Casa OS If the some reason you have installed CasaOS on Raspberry Pi OS and it works fine, but when you try to switch the system to USB to boot, the system fails to boot.