Formatting a hard drive along with the install of a new OS is the best option. The vast majority of operating system installations provide a "format" option as part of the installation process.

The PinePhone and PinePhone Pro smartphones are designed to make it easy to choose your own operating system. While the phones ship with a version of Manjaro Linux featuring the KDE Plasma Mobile user ...

It is very normal to have multiple operating systems installed on a PC. If you need to use Linux and Windows for your work purposes or any other purposes, the obvious option you have is dual-booting ...