If you have the confidence that you have learnt the game without losing much, I believe that you can try your luck with real money.

I haven't heard of anyone winning huge with Blackjack online. You can't make insane profits like a 100+x profit on your deposit amount out of Blackjack. But if you are a bit lucky and are a decent player, you can have a chance to make some profits. I have been playing online Blackjack for years now and the best would be a 3x the deposit amount when I cashed out. So, if you are going to try Blackjack, do avoid the live ones as there will be lot of noobs who hit almost everything which ultimately ruins your luck.