...If I didn’t sell my ETH back then, I could have gained some more lol.
Did you just sell your ETH at $2K because he's your friend or you really had a plan to trade on exchanges?
However, I did advice him to try Binance P2P or other trusted and reputable P2P providers out there.
Why not offer your services instead? You could buy for him and charge a small fee untill he learns how to buy directly without using P2P.