Is it possible to scan a document then edit it in Pages app?

If one has an iPhone connected to the Mac (in this case iOS 16.4.1, macOS Ventura 13.3.1, and Pages v13.0) then one can choose the Pages Insert menu > Import from iPhone > Scan Documents. One must position the camera so that the full document is imaged, and then when one clicks Save in the iOS camera app, the scanned content appears as a Pages PDF document object. This object cannot be edited.

One can select this document object and copy to the clipboard. Then launch Apple's Preview, choosing New from Clipboard and then save it as a PDF. Then you can open it with a PDF Editor (e.g. Nitro PDF Pro) which automatically senses it is a scanned PDF and offers to OCR for you. With the licensed version of Nitro PDF Pro, one can export the OCRd PDF content to Word DOCX, and that in turn, can be opened and translated by Pages into normal Pages document content. Nitro PDF Pro can also scan from an iPhone, thus eliminating the need for the Pages scanning process altogether.

When you scan a document, it becomes an image in a PDF wrapper. Pages is neither a PDF viewer, nor editor, nor offers OCR (optical character recognition) functionality that can get at the text in the image. So no to your question.

However, independent of Pages, Apple does provide a Shortcut action to get text from a PDF and that can be written to a text document, and subsequently opened in Pages — less the original PDF formatting.

There are several true PDF Editors that can use built-in OCR functionality to extract the text from a scanned PDF. Some of these (e.g. Nitro Pdf, PDF Expert) can be found in the Mac App Store with free trials from their vendor websites. If you have a subscriptiong to Adobe Acrobat Pro DC, it too can perform OCR on your scanned PDF.

Another twist is if you control the scanner and it is supported by the paid VueScan Professional application, then you have the option of generating an OCR'd PDF and the OCR'd content in a text file separate from the PDF. That PDF can be opened in Apple's Preview and you then can copy/paste the PDF text content into Pages. This will not be as effective if the PDF is not plain, but form-oriented structured text.

I just tested the first paragraph with the current VueScan Professional and an ancient Canon flatbed scanner on macOS 13.3.1.

If the first paragraph will not work for you, then you will likely need an appropriate PDF Editor.

Although I have OneNote as part of Office 2021 for Mac, I chose not to install it. Does it OCR the PDF in place allowing one to copy/paste the text, as well as resave it as an OCRd PDF? If the latter, and one has Word v16.31 or later, it can convert that particular PDF to a .docx document with a reasonable appearance to the original PDF, thus minimizing subsequent formatting and an easy transition to Pages if one chooses.

Does the free version of OneNote still tie one to Microsoft's OneDrive?

OneNote requires OneDrive but will work offline if there's no internet connection.

OneNote allows a PDF to be attached to a note. OneNote will use OCR to convert the PDF into readable text that can then be copied into a Pages or Word document.

The OCR processed PDF can be saved.

OneNote OCR is extremely accurate.

OneNote OCR is free.

OCR is the name for recognizing an image into text so you can change it using your text editor like pages

https://machow2.com/ocr-for-mac-best-software/

Use the free Microsoft OneNote desktop app for Mac. It supports OCR and allows you to extract text from an image file or PDF:

https://www.onenote.com/download