Creation of a payment system (Internet of the Bank)

Web developer services are required. You need to create a payment system (Internet Bank). We need a payment system (Internet Bank) in which (should) be rubles, dollars, euros and cryptocurrency. Depositors who opened accounts in this system and deposited funds of depositors in this payment system must work. That is, from the amount invested by the depositor funds, the depositor should run in % of the invested amount. (You need to build the code into the system!) so that the system can either collect bonuses or something else. But the point is that the payment system itself would increase the percentage. But not as payyer doubles. Oh, something different. I'm waiting for your answer. Thank you.