Poker is a game of skill and luck. Over time, skill can almost completely eliminate the luck factor, but there is always the possibility of a bad streak. This is true in life as well: being confident in a job interview can get you ahead of someone with a stronger CV, but you can still lose to someone who lies or cheats.
Each player places a bet before the cards are dealt, called an ante or blind bet. Players may also raise the amount of their bet at any point during a hand, which is called raising. If you raise, the other players will choose to either call or fold. Depending on the rules of your particular game, you may be allowed to draw replacement cards from the deck during or after the betting phase.
After the first round of betting (known as the pre-flop), 3 additional cards are dealt face-up to form the flop. These are community cards that can be used by all players to make their best 5-card hand. A player can then win the pot by having a strong hand or by bluffing, forcing other players to fold.
To improve your chances of winning, practice and watch experienced players. Observe how they react to different situations and learn from their mistakes. This will help you develop quick instincts and make better decisions. Practicing and watching will help you learn to spot patterns and identify weak hands.