There are many versions of the game, where the main difference is the number of players in each team, but the most common one, football or soccer, is played by two teams of 11players each fighting to get one ball. The purpose of the game is to send the ball in to the opponents goalpost, a frame approximately 11 meters wide, 2.7 high. To do that, the players can use their all body except arms and hands. The most common way of managing the ball is, obviously, using the feet, but also the head and the chest are widely used. Among the 11 players, one of them is allowed to use the hands and arms to defend their own goalpost, i.e. to stop the ball from going in to it. He is called GOAL KEEPER and can use his hands only in a portion of the game field near his goalpost. The players are not allowed to hold each other or to stop one of the opponents using their hands or arms or by bringing him down with their hands or feet, no tripping is allowed. Dribbling and tackling with the feet are allowed.
To play football could be a little complicated but once you known the game it could be simple. Football is generally played with a team of 11 players. At the front field you have 3 players, known as the Forwards. The main role of these players is to shoot the goal. One is to the left, the centre and the right. The next three players are placed at the centre field. These players generally do the job of passing the ball from the back field to the front field. The next three players are known as the Defenders. These players have the job of only kicking the ball ahead; in short have to protect the ball from scoring a goal. The next player is known as a sweeper. The sweeper's job is to clear the ball from the D area. The last player that completes the team is the Goal keeper. His job is to purely protect the ball from moving into the goal.
You have to be good at it.
Just kick at ball