RemoteFX is not something you can just enable. It requires you to setup Remote Desktop Services with the proper license together with Hyper-V to virtualize a Desktop with an enterprise version of Windows and a supported video card.
Even with all that, performance still isn't great enough for general gaming and there is a noticeable amount of latency and image quality issues.
So just stick with the solutions that actually work, such as Steam or NVidia streaming.