Silly Question on GTA5

Sorry for a dumb question but i have researched everywhere. I played and beat GTA5 on my xbox 360. I fu purchase the game for my xbox one \\same gamertag'' do i have to play the game over again or is my previous stuff, misisons, money etc there? thanks in advance.

You have to start the single-player campaign all over, but you can transfer your online-character to your new Xbox One and thus keeping all your vehicles, apartments, money and so on.