For starters, you need to be running Windows 8.1 or higher since the tool isn't compatible with Windows 7 (or older operating systems). In addition to this restriction, keep in mind that you must have Microsoft Visual Studio 2015 and Python 2.7 installed for the emulator to work.
So that we're all on the same page, Xenia is an emulator that's constantly being developed. Although some games can be emulated correctly (the website lists the ones that are compatible), the majority of the games don't work.
Xenia Emulator is an interesting project because of the simple fact that it's the first Xbox 360 emulator that could become fully functional one day. But, you have to have a computer that's powerful enough to run a video game.
You must have Microsoft Visual Studio and Python 2.7 installed in order to use Xenia.