There are basically two ways you can get involved in a poker game, through tournaments or through cash games. Both are very different in how you should approach them.
These can take the form of anything from six people at a single table (STT – Single Table Tournament) to several thousand people involved at a number of tables (MTT – Multi Table Tournament).
You pay a fixed fee to enter and are given a number of chips to play with. Each player is eliminated when they lose all their chips and the winner is the player with all the chips at the end of the tournament who then takes the first place prize money. There are generally prizes for those finishing as runners up, the number depends on the number of players in the tournament at the start.
In a STT there is only one table and usually a maximum of ten players. In a MTT there can be many tables with the number reducing as players as eliminated until there is one final table left.
These are played at a single table with anything from two (heads up) to ten people. Instead of using chips as in tournament play you play with cash and players are constantly joining and leaving the table. You can stay in the game as long as you have cash.