How to uninstall Windows 10 OEM?

Question

ASUS

Windows 10 OEM needs to be uninstalled. The first thing I tried was to boot from a flash drive. I started the installation, after which I did not have a window for selecting the Windows edition and its bitness, when I wanted to format the hard disk, instead of three disks (system), C and D, several were created ... Namely, MSR and recovery.
How to demolish the pre-installed system and the key sewn into the BIOS?
Thanks in advance!