I wanted to install CentOS on a PC I wasn't using to study Linux. However, my PC didn't come with an optical drive, so I installed it using USB.
Select the version of CentOS from this site and download the ISO file.
Move the downloaded ISO file to a USB memory.
Must be a boot USB to be able to boot from the BIOS. For that, we use software called Refus.
Download & launch Refus. Set as follows and wait until it finishes starting.
Set the boot USB to boot first in the boot settings of the BIOS.
When you start it, the CentOS installation screen should open.