Don Vito Corleone’s youngest son, Michael Corleone, was initially against the “family business” and joins the Marine Corps in World War II after dropping out from college. After his father is attacked by rival gang, he decides to kill the rival gang. Immediately after committing the murders, he runs away in hope to forget it all, but after his wife and his brother are killed, he goes back to New York and become the new head of Corleone family. After moving to New York he marries Kay and promises to make the family legitimate.
Unlike his father who values respect over legitimate. He wants people to respect him and his family using fear. On the other hand, Michael wants to make the family legitimate. Meaning he wants the family to not kill,