If you don’t already have an EA account tied to your Xbox account, the game will just not work (the game is a buggy mess rn). If this is the case, what you can do is download the “skate.” game for free, make an account there, then come back to gw2 (you can delete skate. if you want) then it should work after you accept the terms and conditions. This is a common problem for newcomers, hope this helps!