Hi, this video shows you how you can set up 2 Xbox One consoles so you can share games and also share Xbox Live Gold so you only have to pay for one subscription. Both Xbox consoles can play online at the same time and also play the same game as long as it is downloaded onto the hard drive, you cannot play disc games on both Xbox consoles at the same time. This will definitely save you money especially if you have 2 children/friends etc. that want to both play the same game as you don't have to pay for it twice.
Many thanks Vince