The problem is that according to ToS of all exchanges you have to be 18+ in order to perform such financial operations. Even if you find some exchange that do not require KYC they can easily block your acc if you have any problems. Also sometimes it happens that exchanges implement KYC and freeze all unverified accounts.
Anyway, try to follow the rules.
Instead of giving it to his parents, he can use his parents ID to create an exchange account. I do not think it is illegal thing to do, I have an account which is verified using my wife's ID.
Or just tried to find an exchange without ID verification. Maybe he can try livecoin.net, there are markets for usdc and tusd but the market is so empty