how we can sell and parchase crypto like BTC etc can we deposit directly into our account
You can use exchanges such as Binance or p2p Bisq/Paxful to buy and sell BTC for your fiat currency.
because in my country BTC and all others crypto is not acceptable
If cryptos are banned in your country then you can't use exchanges to buy cryptos,
i her that there are lots of 3rd party platform available for that and also online exchange company corporation
Usage of platforms depends on the legal status of cryptos in your nation and as I said if its banned only leaves you with the option of buying via decentralized P2P like Binance but if you are a complete beginner then you may not feel convenient using Bisq so Please refer through this guide:
[GUIDE] How to buy and sell Bitcoin using Bisq