Is a son's resistance to his father's physical assault considered an act of disobedience (ʿuqūq)? What is the correct course of action for him in such a situation? And is obedience to the father obligatory in personal matters such as education?

What your father did by beating and cursing you is oppression and a forbidden act. However, it does not justify your disobedience, beating, or cursing him, as this is a forbidden act of disobedience and one of the gravest sins. What you should have done was to rid yourself of his harm without beating or cursing him. You must repent, show filial piety towards him, and treat him kindly. You are not obligated to obey him in matters that concern you personally and do not benefit him, such as studying a major you do not desire. This is because "a person is obligated to obey their parents in matters that do not involve disobedience, even if they are disobedient... and this applies to matters that benefit them and do not cause harm." You should gently persuade him and seek help from those whose advice he accepts.