How do ROMs work?
Read-only memory, or ROM, is a type of computer storage containing non-volatile, permanent data that, normally, can only be read, not written to. ROM contains the programming that allows a computer to start up or regenerate each time it is turned on. ... Once data is written on a ROM chip, it cannot be removed.
Read More here: https://www.mexseo.info/2021/07/best-safe-rom-sites.html