Every computer has a BIOS, or Basic Input Output System that tells it to start loading its operating system from somewhere, such as a mass storage device. I have a PC made in 2014 that pretends to load its operating system from mass storage plugged into its USB ports. But its BIOS is too old and does not know how to deal with modern mass storage. My other PC, made in 2018, performs this task effortlessly. Most PCs do not automatically boot off external USB media, instead you have to go into the BIOS to tell it attempt a new boot order. Seems to me it is time to repurpose the older PC and replace it with current hardware. Once upon a time the BIOS was kept in a PROM so you could reprogram it with a new BIOS, but those days are long gone the flurry of planned obsolescence, cheap hardware, and mass marketed appliance level devices.