Should he cut off ties with his father who is opposed to his becoming righteous?
12-3-2023 | IslamWeb
Question:
My father hates me because i don't look at women and wear my trousers above my ankles.The former affects my grades and I fear that he might beat me up and it only gets worse because the teachers tell him.i am 15 should i leave my home and country to live somewhere else although i have no money i live in germany.
Answer:
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad 
is His slave and Messenger.
We ask Allah the Almighty to reward you with the best reward for your keenness to persevere in obedience to Him, and to follow the guidance of the Messenger of Allah . We ask Allah to grant you guidance, piety, chastity, and wealth. We advise you to pray to Allah, the Almighty, for your father to grant him strength, truth, guidance, and insight, and to make him pleased with you.
Perhaps your father doesn't hate your righteousness. Rather, he may fear that you, like some young people, should follow an extremist approach. If you think that this is most likely the case, try to calm down his fears, and let someone reassure him that you are following the path of moderation without extremism.
Your father may think that your dedication to religious duties affects your academic achievement. Therefore, you should prove to him that the opposite is true; that your religiosity is a drive for excellence. Be sure to seek the help of your fellow students who are diligent in their lessons to encourage you to study.
An adult has the right to be independent of his father in terms of livelihood if it is safe for him. Ibn Qudamah 
said in Al-Mughni: “Custody is only established for a child or an insane person. As for a rational adult, there is no custody for him, as he is free to live with the parent he wants. In the case of a man, he may live by himself, as he can do without them. However, it is desirable not to be separated from them, and that his kindness to them should not be cut off.”
Since you do not have money as you mentioned, you should be patient and do your best to be respectful and kind to your father, and be diligent in your studies to make him be pleased with you. Take good company that will support you, and seek strength through piety and patience. Allah the Almighty says (what means): {Indeed, he who fears Allah and is patient, then indeed, Allah does not allow to be lost the reward of those who do good.} [Quran 12:90] This verse came in the context of the story of Prophet Yusuf, peace be upon him, and the elevation he had after patiently and steadfastly enduring affliction. You should also indulge in much remembrance of Allah, for it makes the soul at peace and the mind is calmed. Allah, the Almighty, says (what means): {Unquestionably, by the remembrance of Allah hearts are assured.} [Quran 13:28]
Allah knows best.