There are many different forms of poker. The basic rules of poker state that the high hand wins the pot. You only use five cards no matter how many cards are dealt to you. The lowest hand to win would be a high card. The highest hand a royal flush.
A poker game starts with players being dealt two face-down each. Round of betting follows and three community cards are dealt face-up in the table middle. Another betting round takes place before fourth community card is dealt and there is a further betting round before the fifth community card is dealt. Final round takes place at this point.
To play poker you deal the cards and then match them according to suit or number. A series of 5 consectuative cards is a straight, 5 of the same suit is a flush, and 2 of the same card is a pair.
There are many variations of poker, but they all involve betting on whether the cards you have are better than your opponents'. The first thing to do is to learn the rankings of hands. Then decide if you are betting real money or just playing for fun. Enjoy the game!