15-year-old needs help securing BTC assets without a cold wallet

Hello. I am asking this for a friend… he is 15 years old and has some Bitcoin saved up (a couple thousand USD) but he cannot buy a cold wallet and get it delivered to his house because his parents don’t know he has any crypto assets. He also can’t ask anyone to buy it for him.

How should he protect his funds? He is a bit paranoid reading all these stories on reddit about people loosing all their funds and want to protect them better. He has all his BTC in a single hot wallet on his phone and is getting more and more anxious about loosing his funds each day. Do you guys have any suggestions on how he should protect his funds without a cold wallet?