Because there is no official version, any "FIFA 21 Xbox 360 Download" you find online is likely a modded version of an older game or potentially harmful software. Official Options for Xbox 360 Players

: As of July 29, 2024, the Xbox 360 Store and Marketplace has officially closed. While you can still download previously purchased content, you can no longer buy new digital games or DLC directly through the console.

: The standard digital version available via the EA App or Steam [26].