You must use an emulator like Xenia Canary and load the official Xbox 360 game files (.iso or .xex).
If the hassle of repacks and emulators is too much, or you cannot get the 500MB version to work, consider these legal alternatives that are actually smaller :
: Files labeled "highly compressed" on third-party sites are often used to distribute viruses, miners, or spyware. Platform Compatibility
Don't fall for the 500MB claim. The real file size is over 35 GB, and any smaller file is either a virus or a fake. Stick to legitimate methods: play the physical Xbox One version via backward compatibility, emulate the Xbox 360 version with Xenia, or play the newer, official PC releases like Forza Horizon 4 or 5. These options give you the real experience without any risk to your computer or personal data.