Can vba be used to move code to a new workbook?

You could write code to create code but it might be easier to have a template worksheet with the SelectionChange code in it and copy that to the new workbook.

Yes you can do it, but it would be easier to work with a template worksheet no matter how many workbooks you are creating.

For example to create a new workbook and copy a template worksheet to it:

Dim wbNew As Workbook
Dim wsTemp As Worksheet

    Set wsTemp = ThisWorkbook.Workhsheets("TempSheet")

    Set wbNew = Workbooks.Add

    wsTemp.Copy After:=wbNew.Sheets(wbNew.Sheets.Count)

To add the SelectionChange event to a worksheet in a newly created workbook using code:

Sub CreateWSSelectionChange()
Dim wbNew As Workbook
Dim VBProj As VBIDE.VBProject
Dim VBComp As VBIDE.VBComponent
Dim CodeMod As VBIDE.CodeModule
Dim LineNum As Long

    Set wbNew = Workbooks.Add
    Set VBProj = wbNew.VBProject
    Set VBComp = VBProj.VBComponents("Sheet1")
    Set CodeMod = VBComp.CodeModule

    With CodeMod
        LineNum = .CreateEventProc("SelectionChange", "Worksheet")
        LineNum = LineNum + 1
        .InsertLines LineNum, "    MsgBox ""Hello World!"""
    End With
    
End Sub

That's a very simple example and only creates code for a message box.