Is it possible to earn 2-3 bitcoin by working online with out investing in an year or so...because i am not that financially strong to buy the bitcoin
Not 2 or 3 but surely you can get around 1 bitcoin stsrting with a newbie. On an average a full member gets around 0.07 btc for wearing signature. But it will take you 4 months to reach that mark. Go for some altcoin bounties. Social media campaigns and other services. I think if you do well with some trading on exchanges you can earn 1 bitcoin in an year