How insert a multi-page word/pdf document into another "master" word document?

It's not necessary to create a master document to format a book. Simple section breaks between chapters are enough to create all the formatting you need.

Word has a Master Documents feature, but I have to advice strongly against using it for a permanent set of subdocuments. It's so prone to corruption that Microsoft doesn't even document the feature on any of their pages. It's only safe to use if you create a master document, print it, then delete it.

Having warned you, here's a page that explains how to use it: How to Create a Master Document in Microsoft Word Please keep copies of all your subdocuments in a separate folder, so when the master document corrupts the subdocuments, you have something to go back to.

I can't see how a parent/child document relationship would solve an embedded PDF displaying with only one page.

After embedding an object in Word, double-click on that object to open it in a PDF program to view the other pages.

Or export that PDF pages to separate files or a graphic format, then place each of those on a separate Word page.

Or import the PDF into Word to create Word pages, then past those into your document.

First, the term "Master Document" is the name for a Word feature that you do not want to be using.

Master Documents "Feature" in Microsoft Word

Using the idea of a base document into which others are inserted...

If a pdf is inserted directly into Word, it is an object that can be opened and read by a pdf reader but multiple pages will not be displayed directly within Word. This is as John Korchok told you.

You can, within Word, use File > Open to open a pdf. This converts it to Word format and it is not a pdf file.

Converted documents will have formatting anomalies that will show up when you try to edit.

Or, as suggested by John, you can split the pdf into separate files, one for each page. These could be jpg or pdf.

I have two (or plus) multipage word documents; I would like to insert them into a new word document.

But from this 'new' word-document I would like to be able to scroll through all the pages of the original documents and print them without having to open the original documents (I will only open them if I want to edit them).

As if the inserted word-documents are the chapters of a book and the master document is the book.

Then if I change the chapters the book is automatically updated. And also I can add some extra text content in the master document!!

When I use the "Insert-Object-FromFile" function, only the first page of the attached document appears