Should a young man marry with money from an usurious loan paid by his father, or should he continue to fall into fornication, which he cannot prevent?

Advise the young man and woman to fear Allah, to stay away from the forbidden relationship, and remind them of the verses about lowering the gaze and guarding one's chastity, and the Prophet's command to fast for those who cannot afford to marry. As for the father taking an interest-based loan for marriage, it is impermissible and a major sin, due to the absence of necessity that would permit usury, as alternatives exist. However, if the loan was originally taken for another purpose, then there is no harm if the father gifts from it to his son. Advise the young man to be patient and to stay away from the girl if marriage in a permissible way is not facilitated, to turn to Allah with supplication and fasting, and to seek other alternatives to unlawful money.