One option is, you can buy from Koinex loop or coindcx and then send btc to binance or bittrex. Then you can easily trade between any cryptocurrency. International exchanges are chargiung less fee as well.
Remember: always on 2 factor authentication to void scammers.
Yes that is the simplest way to trade in crypto currency's. but i think local bitcoin is the best among all Indian exchange to buy and sell crypto in fiat.