Remember, a stock option contract is the option to buy 100 shares; that’s why you must multiply the contract by 100 to get the total price. The strike price of INR 300 means that the stock price must rise above INR 300 before the call option is worth anything; furthermore, because the contract is INR 10 per share, the break-even price would be INR 310(INR 300 + INR 10).
Just as there are several ways to skin a cat, there are an unlimited number of option trading strategies available in the futures markets. The method that you choose should be based on your personality, risk capital and risk aversion. Plainly, if you don't have an aggressive personality and a high tolerance for pain, you probably shouldn't be employing a futures and options trading strategy that involves elevated risks. Doing so will often results in panic liquidation of trades at inopportune times as well as other unsound emotional decisions.
When buying or selling options, the investor or trader has the right to exercise that option at any point up until the expiration date - so simply buying or selling an option doesn't mean you actually have to exercise it at the buy/sell point. Because of this system, options are considered derivative securities - which means their price is derived from something else (in this case, from the value of assets like the market, securities or other underlying instruments). For this reason, options are often considered less risky than stocks (if used correctly).