Is it permissible to take the usurious increment resulting from an investment certificate as a gift from the father, or to leave it for the family to prevent discord and the father's anger, knowing that the father is responsible for the questioner's expenses?

The investment certificates issued by usurious banks, of all types (A, B, C), are Islamically forbidden, because they represent usurious loans guaranteed with interest, and not legitimate mudarabah (profit-sharing partnership). The Islamic Fiqh Academy has issued a fatwa prohibiting bonds that represent an obligation to pay a sum with interest, whether the issuing entity is private or public. Its ruling is not changed by calling them "certificates" or "investment sukuk," or by calling the interest "profit" or "yield." This prohibition also includes zero-coupon bonds and prize bonds. Whoever has dealt with them is obligated to repent and dispose of the forbidden excess by spending it on charitable causes, and it is not permissible for him to benefit from it. If the certificates are issued in your name, the excess is yours, and you must dispose of it. It can be given to a poor person or a debtor for the purpose of disposal, not as charity.