I heard from someone that if you want to earn money without any investment then you should go to bitcointalk. But he also told me to keep alert. I created an account. I am feeling very confused but I am not able to understand anything.
Welcome. But your friend lied to you because he did not tell you how everything works here and how you will go about making money on the BitcoinTalk forum. Even aside from the signature campaigns for you to earn money here, you need to be known by forum members before someone can give you a project to handle here; you are still a newcomer. I doubt if you have already studied the forum rules and regulations the way you suppose, so go and do that before you will think of earning in the forum.