Must I repay the bank loan in full now that I have the amount, or should I continue paying installments, considering I don't have an emergency fund, and what is the ruling on Zakat for this money?

There is no harm for you in paying off the bank debt in installments according to the contract, and you are not obliged to expedite the payment, although it is recommended to hasten in order to clear your liability. Your dealings with your father have no relation to your dealings with the bank. The saved amount is subject to Zakat (definition) if it reaches the nisab (definition) and a full year has passed over it, and its due amount is a quarter of a tenth. The majority of scholars hold that if a debt consumes what a person possesses, Zakat is not obligatory upon him.