Is there a way to open a PDF as an InDesign document (like one would right click a picture and click "open with PhotoShop")? I am not sure if there is a way to do this without an outside source... I am just looking to see if there is a way to do this. TIA!
InDesign works very well with PDFs, but as uneditable graphics. A PDF page can be placed into InDesign as a graphic (including as a full page) and this is a recommended workflow. You can't edit but could mask and patch.
There are third party applications and plug-ins for InDesign that purport to convert PDF files into editable InDesign documents. The output of such conversions tends to be only a rough starting point from which you should expect to do significant edits to provide a workable InDesign document.