It's a Insider Build! \ You could try to 'upgrade' from Windows 7 SP1 to it, but AFAIK, you need to sign in as Insider First and use a MS Account, if follow the MS Rules! There other ways, just those are not as MS expect. It's simp[ly up to you what way you like to go. Check out on this Windows 10 Foorum of MDL by reading the relevant posts.
looks like Im going to be stuck with windows 8.1. I use slingplayer pro hd for watching my HD dvr on my pc. in windows 10 builds. the software has hard time sometimes syncing with the dvr. resulting in skipping and flashing black screen. I get artifacts in older games or they dont run. mostly seems to happen to games that was badly coded to start with. steam software lags sometimes. this is mostly because I have alot of games and causing steam to lag. they issued a beta update for it. but still does it for me. the operating system it self sometime lags.