how to add code programmatically to a macro for a button

[Tina]

hi,
i have coded the following lines, but i am not sure of how to insert
code within the macro Button_click. Also I am not sure of what
"Module1" is.
can someone help me please?
TIA!
Tina
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For i = 0 To 4
ActiveSheet.Buttons.Add(50 + i * 100, 10, 80, 25).Select
Selection.OnAction = "Button_click"
Selection.Characters.Text = "Play Game" & i

Dim VBCodeMod As CodeModule
Dim LineNum As Long

Set VBCodeMod =
ThisWorkbook.VBProject.VBComponents_("Module1").CodeModule

With VBCodeMod
LineNum = .CountOfLines + 1

*** what do i write here to display a messagebox?
*** i want to add code to the Button_click macro.

End With
ActiveSheet.Range("A1").Select
Next i