VBA Moving Worksheet [ No workbook selected ]

i have 3 working files
E1 - contains button command that uses my UDF and Saved Macro
E2 - source
E3 - target

what i needed is using E1 workbook, click the button to copy/move my sheet from E2 to E3
i use the E1 as my jump off workbook for all my Macro / VBA / UDF
someone suggested that i just run from my E2 files my Macro / VBA / UDF but E2 workbook is dynamically created thus the need of the third E1 workbook as main form (somewhat)

snippet of my code

    Set TargetWBook = Workbooks.Open(TargetFilename)
    Set SourceWBook = Workbooks.Open(SourceFilename)
    
    SourceWBook.Worksheets("newSource").Activate
    TargetWBook.Worksheets("oldTarget").Activate
    
    Worksheets(1).Select
    SourceWBook.RefreshAll
    TargetWBook.RefreshAll

    Sheets(E2).Copy Before:=Workbooks(E3).Sheets(1)