You had bitcoin and altcoin but you didn't know how to exchange them? You had a lot of coins and you give access to some random guy. Feeling sorry for OP. It seems you are from Bangladesh, like me. I have seen most of the people here involved with crypto do not have enough knowledge on crypto but they are really not that dumb. Good luck.
The scam thing is everywhere. It is not only exclusive to Bangladesh although that country is known for its high level of corruption. It is good that the OP learned a lesson from that experience and has since moved on, still dreaming big. Do not give up on your dreams. And next time hold your private keys like gold.