PC player here can you guys answer some questions?

So I decided to buy the X1 because I started to notice that Microsoft is starting to support PC more and more I've always have had love for the Forza series but I never had the push to buy one just for this series until now with the PC support they are giving I figured I should support them.

So here is my question I'm buying the Forza edition x1 and it says I can download the game from Xbox live but can I also download other games from XBL? Like forza horizon 2? And how about new games on release? I prefer to download games like I do on Steam is it possible to do this on Xbox?