1. Is a young man sinful for not wanting to live with his parents? 2. Is he obligated to complete his worldly studies when he desires to dedicate himself to seeking Islamic knowledge without his mother's approval? 3. Is he obligated to seek his parents' permission to work? 4. Is he sinful for disobeying his parents regarding entering a co-educational university?

Answers to your second and third questions have been provided, as has the answer regarding obedience to parents concerning studying at mixed-gender universities. There is no sin upon the son merely for disliking to live with his parents, as long as he does not harm them by this and fulfills his duty of dutifulness towards them. Nevertheless, we advise you to reconsider your interactions with your parents and improve your relationship with them before seeking sacred knowledge, because dutifulness to parents is a great obligation.