How to pass parameters to a Blueprint function called from C++?

I’ve just started to learn Unreal Engine.

I have created HUD using UMG and now I want to access a function that I have defined on it using C++. The code to get the function is:

 UFUnction* Func = Obj->GetClass()->FindFunction(FName("FuncName"));
 if(Func == nullptr){return;}
 FStructOnScope FuncParam(Func);
 UProperty* ReturnProp = nullptr;
 for (TFieldIterator<UProperty> It(Func); It; ++It)
     UProperty* Prop = *It;
     if (Prop->HasAnyPropertyFlags(CPF_ReturnParm))
         ReturnProp = Prop;
         //FillParam here            
 Obj->ProcessEvent(Func, FuncParam.GetStructMemory());

But… I don’t know how to //Fillparam here.

How can I fill the FuncParam with the parameters that I need to pass?