Is zakat obligatory on land purchased in installments for the purpose of trade, where the seller's ownership remains until the last installment is paid, and what is the amount of this zakat, and is it permissible to give zakat to one's father without informing him of that?

If a contract for the purchase of land is concluded between you and the bank, the land becomes your property. However, if you cannot dispose of it until you complete the installments, then no zakat is due on you, due to the incompleteness of ownership. But if you can dispose of it, then zakat is obligatory on it as zakat on trade goods (2.5%) on its full value, because debt does not prevent the obligation of zakat. The zakat is based on the market value of the land on the day zakat becomes due. As long as your intention is to trade in it, zakat is obligatory on you. If your intention changes to residing in it, then no zakat is due. It is not permissible to disburse zakat to the zakat payer's ascendants or descendants.