Me and a friend 1 account license?

Ok so me and a guy are really looking into developing a game together now me and him both have unity free with this license can he sign in to my account and work on the game and vice versa with the unity free license or do we need a paid license p.s. I’m 15 and he’s 14 so we are not able to purchase unity until maybe later in age I’m just trying to figure out how this would work for me and him

You don’t need to purchase Unity pro until you earn more than $100000 a year. Since you’re 15 i don’t think that should apply, does it? ^^ You and your friend can use seperate free licenses.