Hi Sandeep,
Calling a sub-routine within dynamic actions is perform by the F command.
First, you need to ask your ABAP developer to create a routine within a program, for example: see routine GET_DATE in the program HBRDYNMS - in order to call this routine you create a new F type record in T588Z with: GET_DATE(HBRDYNMS) .
You may debug this routine in order to check if it calls the RFC properly.
Regards,
Liran