thanks for your responses.
i understand it sounds strange, but i would invest the dollar in crypto on coinbase anyway and he does owns btc. so i was asking myself, why not send his btc directly to my coinbase. instead of receiving cash to my bank account, transferring cash to my coinbase and then trading cash for crypto.
i was unsure because for bank transfers coinbase wants the name of the bank account to match with the coinbase profile.
If your end goal is to store your funds in bitcoin, why not just have your friend send bitcoin directly to a non-custodial wallet? There are many advantages to not sending all your bitcoin directly to (or through) your Coinbase account, self-custody being the most significant of them.