One of these. The issue you have is that the parameter Name is a label control that should include the index too. It is not a control name; but an actual control. That's what is expected
1. This way
Code:
Private Sub Command2_Click()
Tada Label2(0), 0
End Sub
Private Function Tada(Name As Label, Tes As Integer)
Name.Caption = Tes
End Function
2. Or this way
Code:
Private Sub Command2_Click()
Tada "Label2", 0
End Sub
Private Function Tada(Name As String, Tes As Integer)
Me.Controls(Name)(Tes).Caption = Tes
End Function