Second Xbox One account?

I have been playing a game for some time where it is not possible to use multiple saves. When I log in to my One with a new email, there are no saves from the first account? So the game remains on the other account and I can start again on the second account? Or does it have anything to do with the memory of the One, that the game is also played through on the new account? If I start a new game on the second account, will the savegame in the first one be correct?

New Account = New Score

So it works.

Great thank you.