@Rizstien, I use Coinbase, they take credit/debit cards but charge 3.99% as opposed to 1.49% if you link a bank account. There is a verification process though, don't know how long it takes for credit cards. It took 3 days for my bank account to be verified. Then another 7 business days before transferred funds are available. Credit cards may take a lot less time but cost more to buy coins.