Is it permissible to eat, drink, wear, and spend on studies from family money mixed with usury, and is it permissible to take luxuries from it?

If your father's money is mixed (lawful and unlawful), it is permissible for you to benefit from it even if you are not in need. However, if all his money is unlawful, it is not permissible to benefit from it except to the extent of need. Some scholars, however, hold the view that it is permissible to benefit from it even if not in need, and the sin is upon him, not upon you.