Why do max and his dad leave the apartment in freak the mighty?

In "Freak the Mighty," Max and his dad leave the apartment because Max's dad, who has a troubled past, is released from prison and wants to take Max with him. Max feels unsafe and uncomfortable with the idea of living with his father, who has shown violent tendencies in the past. This decision is fueled by Max's desire to escape a potentially dangerous situation and find safety, ultimately leading him to seek refuge with his friend Kevin (Freak) and his mother.