Well i actually didn't mean that. From what i heard he did something illegal. I'm just wondering what exactly he did. He claimed to be something like a broker.

Hello.
I'm a new user and I'm kinda familiar to cryptocurrencies. Recently my cousin's wallet got blocked and he got arrested because he owed someone some money and since his wallet was blocked he couldn't pay him.
He claimed that he had 600000$ in his wallet and he made that money in a few months! He was making 2000$ per day.
He said he was trading cryptocurrencies (probably buying them for people and getting a wage for that) with some specific Asian countries.
Unfortunately he didn't give much detail. So now I'm here to ask, is that even possible?
If yes, how exactly?