Autofill help

I am having trouble and I think the answer is simple, but I cannot find it or figure it out. I have a table, say 3 rows x 3 columns. I have vba that when I doubleclick on a row, it inserts a new row below where I clicked and copies the values from the cells above to the new row. What I want is code for column 3 to fill the cell below so the number in say cell C1 increases by 1 and is put in the new cell C2. This needs to be variable as the table grows, so that if I doubleclick on row 20, which then adds a new row below and copies the values from above except for column 3, which will autofill the cell value from the row clicked on, add 1 and put that value in the cell below. Thanks for any help.

Sure, pretty simple code, but it's the autofill I can't figure out. So the code inserted a row and copied the cells, thus C3=C2, but what I want is when it
inserts the new row, it fills like C7 did from C6.

Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
Cancel = True   'Eliminate Edit status due to doubleclick

    ActiveCell.Offset(1, 0).EntireRow.Insert
    ActiveCell.EntireRow.Copy ActiveCell.Offset(1, 0).EntireRow
    
End Sub

I am trying this code, which is close, but it puts the value at the end of the column, not in the blank cell in the newly created row.

Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
Dim LR As Long
Cancel = True   'Eliminate Edit status due to doubleclick

    ActiveCell.Offset(1, 0).EntireRow.Insert
    ActiveCell.EntireRow.Copy ActiveCell.Offset(1, 0).EntireRow
    ActiveCell.Offset(1, 0).ClearContents
   
LR = Range("G" & Rows.Count).End(xlUp).Row
Range("G" & LR).autofill Destination:=Range("G" & LR).Resize(2)

End Sub

Originally Posted by mike7952

Maybe this

With Target
    .Offset(1).EntireRow.Insert
    Range("a" & .Row).Resize(, 2).Copy Range("a" & .Row).Offset(1).Resize(, 2)
    Range("c" & .Row).AutoFill Destination:=Range("c" & .Row & ":" & "c" & .Offset(1).Row)
End With

Thanks mike7952! Pretty well what I need, other than column B not copying, but I might be able to get that. I tried it in combo with what I had and it seemed to work. Great!

Originally Posted by mike7952

On your uploaded example workbook column B is coping for me

Yes it does and now I have it figured out for the true table I am using! Thanks!!