Incrementing Invoice Numbers Using Macros

I currently have a project i am working on based on a invoice system and in my case it is to do with Van rentals. what i am looking to do is create a macro so that when the user clicks the order van button, it brings them to the order page and automatically creates an invoice number which is automatically added to the invoice database along with the customers details and the date of the invoice in a different sheet.

i have been browsing various forums and tutorial and have come across an a piece of code that is incrementing numbers each time the button is clicked. I can add the first set of details to the invoice database however i am unable to create a new row which copies the formulas and just change the invoice number as it is incremented - it just copies the same number

Now i am a complete novice in using VB and i have knowledge to an extent using excel. Is it possible to do that?

Sub test()
'
' test Macro
Sheets("Invoice List").Visible = True
Sheets("Customer Menu").Select
ActiveWindow.SelectedSheets.Visible = False
Sheets("Customer Van Order Form").Visible = True
ActiveWindow.SmallScroll Down:=-12
Sheets("Invoice List").Select
ActiveCell.FormulaR1C1 = "='Customer Van Order Form'!R[7]C[6]:R[7]C[7]"
ActiveCell.FormulaR1C1 = "='Customer Van Order Form'!R[7]C[6]"
Range("B2").Select.............