A live dealer poker game functions like any other poker game that a player would play online, and the main difference is that instead of a machine dealing the cards and taking the bets, an actual dealer does that.
Players register for a poker match, and a dealer welcomes them all. All participants can see each other through the video stream and as they place bets. The dealer will most of the time be on the floor of the casino running the entire game.
They will deal and watch over each round and announce the winner when the game ends.