I have had a really bad experience with the garbage vitalsource calls ebook reader, does anyone know a way to convert the files?

I tried searching but the best method I have heard is if the book has printing enable (depends I think on a toggle to the uploader and if it is an embed pdf or epub) you can get the app to sent the outline of the document to fake a printer, I couldnt find anything to convert the vbk files into pdfs or epubs that was at least updated within 7 years which means probably none of them work at all