How should a son deal with his unjust father who harms his family, accumulates debts, and instigates problems?

Allah created mercy and compassion in souls as an innate disposition (fitra), the strongest of which is the mercy of parents towards their children. One who is not characterized by it is outside of this disposition, like stones in their hardness. The main reason for the harshness of fathers is religion and environment. Despite the father's harshness, Allah commanded kindness and good treatment towards him, and not to obey him in disobedience. To deal with a father's harshness, it is recommended to be patient, treat him well, avoid what angers him, strive for his guidance through appropriate means, and supplicate for him.