Explain how Macbeth changes over the course of the play?

Macbeth at the start is worried about the murder of king Duncan using a quote to lady Macbeth 'we will proceed no further in this business' this shows that he is worried about the murder he will later commit, later on in act 2 he becomes more powerful and almost wants to be as bad as the famous tyrant who was famous in Rome for being a rapist

this is just a brief summary

The first of the witches' prophecies bring out his ambitious nature, but he struggles with killing the king. By attacking his manhood, Lady Macbeth convinces him to committ the first of his evil deeds. Macbeth's evil deed causes him to suffer from fear and guilt, which leads to even more evil crimes.