I wanna ask a question about publication of my game.

If i use my personal account to create my game in unreal engine and use all the assets which i have collected through the years, and publish the game with a different account. Do i own the game or do i need to create a different epic account and make my game there and publish using that account. But i will loose all my assets. Also Can anyone tell me about copyrights and licensing for publishing on steam or epic games? Which assets can i use and which i cannot.