To play legally, you should own a physical copy of the game and dump the game files (the "ROM" or "ISO") yourself. System Requirements for Emulation
Fight Night Champion is one of the best boxing games ever made — great physics, gripping story mode, and tight controls. But on PC, there's no legitimate way to get it. Beware of scams. Instead, try Undisputed for a modern, legal boxing experience. fight night champion pc registration code link