Poker is a game that involves a mixture of luck, psychology and mathematics. While the outcome of a particular hand does depend on chance, most of the decisions that players make are chosen on the basis of expected value calculations and other considerations involving probability and game theory.
After each player has two cards, betting begins. Each player can choose to either call the bet made by the person before them, or raise it. In addition, a player can fold, putting their cards face down and leaving the table for the next deal.
If you are holding a high hand, it is often a good idea to open raise preflop, even if the people ahead of you have limped. This can encourage your opponents to bluff and give you a better chance of winning the pot.
It is also a good idea to be very selective about the hands that you play. It is best to avoid playing high cards like suited aces and kings. Unless the board is very favorable, they will likely lose to any other high hand.
You should also try to get familiar with the different types of hands that your opponent could have, and work out what their ranges are. While new players tend to try to put their opponent on a specific hand, more experienced players will often work out the entire selection of hands that their opponent could have, and then calculate how likely it is that their own hand beats that range.