If you have created your own SAP function module, you can use this with the following VBA code.
Sub FunctionModule()
'Variables Definition
Dim MyFunc As Object
Dim E_INSERTED As Object
Dim E_MODIFIED As Object
Dim DATA As Object
Set MyFunc = R3.Add("Z_RSDRI_UPDATE_LCP") 'FunctionModule Name in SAP BW
Set E_INSERTED = MyFunc.imports("E_INSERTED") 'InsertFunction in SAP BW
Set E_MODIFIED = MyFunc.imports("E_MODIFIED") 'ModifyFunction in SAP BW
Set DATA = MyFunc.tables("I_T_DATA") 'Table to store data and write to BW.
'Add data
DATA.Rows.Add 'add new data
rowDATA.Value(1, 1) = Sheet1.Cells(1, 10).Value 'First Cell of the data table is filled with the value from Sheet1.Cells(1,10)
'Call Insert or Modify
Result = MyFunc.CALL
'Message to the User
If Result = True Then
MsgBox "Insert Rows: " & E_INSERTED.Value & " Modify Rows: " & E_MODIFIED.Value, vbInformation
Else
MsgBox MyFunc.EXCEPTION 'Exception
End If
End Sub