You can look for various digital currency exchanges to buy bitcoin.
You can purchase Bitcoins with a credit card. Coinbase.com and Coindesk.com are the most popular exchanges. They also offer tutorials on digital currencies.
In India, you can purchase Bitcoin from Zebpay exchange. Zebpay has Android and iPhone app which lets you link your bank account for quick transfers.
You can buy Bitcoins by making a payment to Zebpay’s bank account. You can also withdraw the money to your bank account, and track data on Bitcoin valuation in the country.
There is a KYC requirement, and you need to verify your ID by simply clicking a photo of your PAN card.
Unocoin, another India-based exchange, lets you trade Bitcoins. They can help you buy, sell, store, use and accept bitcoin. The company claims it has over 1,50,000 customers
Note: Since the legality of Bitcoins is constantly evolving, kindly check the official notification from Reserve Bank of India for more details – https://www.rbi.org.in/