Alright sorry I miss worded it, what I ment was that I didn’t know what a .sln file was and I had to go back to the readme that the downloaded folder came with but I found nothing so I tried the link
that took me to the “Getting up and running” and it turned out it was the Visual Studio file that was generated.
So after a long wait of building the Unreal Engine worked and the UWP is now in the supported platforms so this worked out successfully.