Yes Mr Amit Kumar You can buy and sell the same stock every day. There is no limit/limitation to such a trading practice. In fact, in good old days of physiscal shares, I knew of a few traders who do trading only in one stock, all through the year - say for example, reliance, tata steel, acc, telco ( tata motors ) itc etc. They just hold some shares of these companies and keep on buying and selling shares, booking some profits.
with online trading and demat form of shares, it has become even more easier. Just note down the pivot, support and resistance levels of your stock for a given day and keep trading as per those levels and the market/scrip trend