Learn to play Blackjack for fun before you hit the tables. Blackjack is a game of both luck and skill. You are going to have to know the rules as well as the unwritten book of no no's before you get on a table.
How to Learn To Play Blackjack
The best way to learn to play is to sit down and start playing without money involved. If you have a friend that knows how to play, then you are set. It should not take long for you to catch on to the general rules.
If you don't have a knowledgeable friend, then go online. The internet will guide you to sites that will teach you the rules as well as a general strategy. Everyone seems to play different, but there are some strategies that everyone uses. If you don't play that way, you could get an entire table mad at you for blowing a hand.
You can learn to play Blackjack through a friend, but it is not until you have money on the line that you really learn the ways of the game. You tend to think much more and be more observant when you money is on the line as opposed to playing for free. So learn the rules and the way of the table then set out to gamble.