Texas Hold’em is a very famous format of poker. If you are a beginner and want to play Texas Hold’em poker, then you have to know the rules first. The systematic rules of Texas Hold’em are here as follows:
1. First, the dealer shuffles a full deck of card (52 cards) and deals every player 2 cards each. The rest of the deck is kept unchanged.
2. The player sitting left to the dealer pays small blind and the player left to the small blind pays big blind.
3. The player sitting left to the big blind starts the game. He has three options now: Bet, Fold and Raise. Thus begins the first round that is called as “Pre-flop Round”.
4. If there is more than one player left on the table after the first betting round ends, the dealer puts a card apart faced down which is called as the “Burn Card”. Then he takes three cards and puts them facing up so that everyone can see them. Preferably, it is kept at the middle of the table. It is called as “Flop”. All the players use these three cards for increasing their hand rank.
5. The player who was left to the big blind starts this round too. If he has already folded or played all-in, then the player left to him (open for betting) starts the round.
6. Every player will have any of these four options: Fold, Check, bet and Raise (Often, there’s another option named “Call”. It is actually same as bet when you are betting exactly the same amount as your previous player). Players will decide them according to their card and betting status.
7. If there is more than one player left on the table after the second round ends, the dealer puts another card apart faced down. It is another “Burn Card”. Then he takes one card from the deck and puts it facing up beside flop. It is known as “Turn”. Players use it for the same purpose as the Flop.
8. The player who is sitting left to the big blind starts this round again. If he has folded or played all-in already, then the player left to him (open for betting) starts the round. Players will have the same options as the second round.
9. Once the third round finishes and there is more than one player left on the table, the dealer takes another card apart faced down, which is the last “Burn Card”. Then he takes one card from the deck and puts it beside the turn facing up. It is referred as “River”. It is used exactly same as the Flop and Turn.
10. The player who is still available to bet, and is left to the big blind starts this round. The options are the same as the Flop and the Turn.
11. When the fourth round finishes, players will show their cards and considering them, the strongest hand will win the pot. People call this “Showdown”. Thus, a poker hand finishes. The player sitting left to the current dealer becomes the new dealer and everything starts from step 1.
12. The strengths of poker hands in Texas Hold’em are as follows (Highest to Lowest):

Five of a kind
Royal Flash
Straight Flash
Four of a kind
Full House
Flash
Straight
Three of a kind
Two pairs
One pair
High Card

These are the normal and regular rules. There are different situations where different in-game rules may apply. These rules vary depending on the situation. You have to learn them from your own experience.