[Excel] adding a row to spreadsheet want to update my code

[sarahmay]

Hi all

I'm not confident with VBA as yet and have simply been creating macro's and then found the need to edit them, so am gradually exploring VBA and what can be done with it.

I currently have a spreadsheet with column A containing staff names. I then have calculations set up to track their working patterns.
I have created a macro that inserts a column at column f and then updates all of my formulae accordingly for example range (d3:d123).

However, when I add or remove staff this changes the final row reference by one or two digits and I want to know if there is a way that my code re-written to update automatically and amend my range:

here is my code, highlighted are the bits that are variable:

 
    Columns("F:F").Select
    Selection.Insert Shift:=xlToRight
    Range("G2").Select
    Selection.AutoFill Destination:=Range("F2:G2"), Type:=xlFillDefault
    Range("F2:G2").Select
    Columns("F:F").EntireColumn.AutoFit
      
    Range("B4").Select
    ActiveCell.FormulaR1C1 = "=COUNTA(RC[4]:RC[17])"
    Range("B4").Select
    Selection.AutoFill Destination:=Range("B4:B123"), Type:=xlFillDefault
    Range("B4:B123").Select
       Range("D4").Select
    ActiveCell.FormulaR1C1 = "=COUNTA(RC[2]:RC[29])"
    Range("D4").Select
    Selection.AutoFill Destination:=Range("D4:D123"), Type:=xlFillDefault
    Range("D4:D123").Select
    
    Range("H2").Select
    Selection.AutoFill Destination:=Range("G2:H2"), Type:=xlFillDefault
    Range("G2:H2").Select
    Columns("G:G").Select
    Selection.Copy
    Columns("F:F").Select
    
    Selection.PasteSpecial Paste:=xlPasteFormats, Operation:=xlNone, _
        SkipBlanks:=False, Transpose:=False
    Application.CutCopyMode = False
     Range("G124").Select
    Application.CutCopyMode = False
    Selection.AutoFill Destination:=Range("F124:G124"), Type:=xlFillDefault
    Range("F124:G124").Select
       Range("F4").Select
End Sub

Thank you all in advance

ETA a bit of gratitude goes a long way