Unlike fake emulators, Xenia is a research project that does not require you to download a "BIOS.rar".
If your goal is simply to play Xbox 360 games on your PC, here are your legit options: Xbox 360 Emulator 3.2.4 Bios.rar Download
A genuine BIOS file for consoles that require it (like PS3 or PS2) is a .bin or .rom file, not an executable. Unlike fake emulators, Xenia is a research project
The software often labeled as is widely considered a scam or malware by the emulation community. Unlike fake emulators