Can you be more specific?
This is the final act, and last scene in the play. In this scene, Macbeth and Macduff finally meet up. Macbeth has just learned that one of the witches' predictions has come true - Birnam Wood (the English army, so vast it looked like an entire woods moving) came up to the castle. Macbeth still thought he was safe, however, because the witches also told him "no one born of woman" could harm him. In this scene, Macduff tells Macbeth that HE was born by Caesarian section (so not really born of woman in the normal way - he was cut out of his mother's womb). Macbeth at first refuses to fight Macduff because he has already killed all of Macduff's family. At the beginning of the scene, he says he is not going to be like one of those Romans and fall on his sword (i.e. kill himself), but then he refuses to fight Macduff for the reasons I have already mentioned. When Macduff reveals the details of his birth, however, Macbeth decides he is going to go down fighting, but Macduff eventually kills him. He enters with Macbeth's severed head at the end of the scene. Macbeth had refused to surrender to Macduff.
The scene ends with Malcolm being restored to his rightful place as king of Scotland.