VB6 exe calling VC++ Windows forms application

I should make VC++ Windows Forms Application and VB6 program(exe file) will call it passing some parameters, for example, gain(integer), offset(integer), min(integer), max(integer).

VC++ WFA should run on the top most when it is called and returns some values, for example, file name(sting), status(integer)

How do I implement in VB6 and VC++ both side?