How do I execute instructions only if the cell value change?

I have a ByVal code to clear the contents of a specific range inside a table, it works. But I need to add a condition for the instructions execute if the RANGE VALUE (content) change, not if I only place the cursor on it.

Also, someone knows how to reference a table column in VBA? Now I'm using an estimated range "C1:C999" but I'll like to use his name "A_[OPERATION]".

This is the code:

Private Sub Worksheet_SelectionChange(ByVal Target As Range)

   If Not Application.Intersect(Range("C1:C999"), Range(Target.Address)) Is Nothing Then
    
       Range(Selection, Selection.End(xlToRight)).ClearContents

   End If

End Sub

A Worksheet Change

• Adjust the table name (tName) and the header (column) name (hName).
• I have adjusted it to clear contents in the cells after the column.
• If you really need to clear the contents of the column too, then replace cel.Offset(, 1) with cel.
• In a table, the current setup will automatically clear the contents of all the cells to the right of the specified column, if a value in the column is manually or via VBA changed. This will not work if the column contains formulas. Non-contiguous deletions are also supported.

The code

Option Explicit

Private Sub Worksheet_Change(ByVal Target As Range)
    
    Const ProcName As String = "Worksheet_Change"
    On Error GoTo clearError
    
    Const tName As String = "A_"
    Const hName As String = "OPERATION"
    
    Dim rng As Range
    Set rng = Range(tName & "[" & hName & "]")
    Set rng = Intersect(rng, Target)
    If rng Is Nothing Then GoTo ProcExit
    
    Application.EnableEvents = False
    
    With ListObjects(tName).HeaderRowRange
        Dim LastColumn As Long
        LastColumn = .Columns(.Columns.Count).Column
    End With
    Dim cel As Range
    For Each rng In rng.Areas
        For Each cel In rng.Cells
            With cel.Offset(, 1)
                .Resize(, LastColumn - .Column + 1).ClearContents
            End With
        Next cel
    Next rng

CleanExit:
    Application.EnableEvents = True
    GoTo ProcExit

clearError:
    Debug.Print "'" & ProcName & "': " & vbLf _
              & "    " & "Run-time error '" & Err.Number & "':" & vbLf _
              & "        " & Err.Description
    On Error GoTo 0
    GoTo CleanExit

ProcExit:

End Sub