Option Explicit

Sub Test3()
Dim answer As Variant
  answer = MsgBox("Are you certain these cells are to be deleted ?", vbYesNo + vbQuestion, "Delete Cells ?")
  If answer = vbYes Then
      Call Test1
   Else
     Exit Sub
End If
End Sub

Sub Test1()
   'Code here to delete or clear cells
   MsgBox "Running macro"
End Sub