How do we attach fast formula with element and recover loan amount

Hi All,

In Ebiz we used to write fast formula and attach it with element for payroll processing. I would like to know where exactly we attach formula in oracle cloud payroll. When I create an element, I see some formulas are already associated with element but don't find a place to attach our own formula that will have calculation logic.

Another thing I would like to know is how do we attach indirect elements automatically to workers to recover loan (in ebiz we had a place to attach indirect elements in formula result section).

For example, requirement is to attach an earning element "CAR LOAN" to employee manually and from the next month it should automatically attach another element "CAN LOAN RECOVERY" and then finally stop this element once loan amount is fully recovered.