Does the debt of prayer and fasting fall away from the father with his repentance and commitment to worship and his distress from fasting, and what should he do with usurious money he acquired unknowingly of its prohibition, and is it permissible for him to donate it to mosques or give it to a beggar who may not be in need?

We ask Allah to accept your father's repentance and forgive him. As for the missed prayers and fasts: if he abandoned them out of denial (of their obligation), then he is not required to make them up according to the majority of scholars, because denying them is disbelief, and an apostate, if he embraces Islam, is not required to make up what he missed.

However, if he abandoned them due to laziness: if he continuously abandoned prayer for twenty years without praying, he is not required to make them up. But if he prayed sometimes and abandoned sometimes, he is required to make up what he missed.

Regarding usury (riba), he must disburse it to the poor, the needy, and for public welfare with the intention of getting rid of it, not as charity.