Searching for old game downloads is a minefield. If you are looking for the pre-patched version (where someone else already combined the ROM and the hack), be cautious.
Since this is a fan-made project, it is typically distributed as either a pre-patched ISO or an patch file that must be applied to an original Yu-Gi-Oh! Forbidden Memories ROM. Recommended Download Sources Yugioh Forbidden Memories 2 Ultimate Download
The search for Yu-Gi-Oh! Forbidden Memories 2 is ultimately a search for a lost feeling: the raw, unfair, magical difficulty of late 90s card games. Thanks to the "Ultimate Download" community, that feeling is alive and well on your PC. Searching for old game downloads is a minefield
Popular examples include “Forbidden Memories: Rebirth,” “Ultimate Edition,” or “Project FM2.” When a site offers an “Ultimate Download,” it is likely one of these modded ROMs. Forbidden Memories ROM
Because you are searching for an "Ultimate Download," you want the file to work immediately. Here is the standard workflow used by the community. Note: You should only download ROMs if you own an original copy of the game.