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.
The Prophet said: “Allaah has cursed the one who consumes Riba, the one who gives it to others, the one who records it and the one who witnesses it (its transaction)”, and he said: “All of them are equal in sin.” [Muslim]
So, whoever works in facilitating or performing Riba (interest and/or usury) transactions in banks or other institutions is included in this curse. The money that the worker gets as wages in a Riba bank for his work is unlawful and he is not permitted to use it or offer it to others (family or relatives). So, if one knows that the origin of the money is completely Haram (unlawful), or partially then he should not eat from it. As for paying the study fees, this can be considered as permissible if the person is in dire need to study and he does not have any other means to pay these tuition fees.
But you should let your father know the authentic Islamic texts which state that working in such banks is a great danger and he should look for a lawful job. This is actually part of your love and respect for him as your father.
Allah knows best.