You can delete pages from a PDF on a Mac using the Preview app. You can also add pages to a PDF in two ways with Preview.

Learn how to add page numbers to PDF files using free online tools or PC software. You can set position, font, etc., for page numbering.

Then select Insert Pages > Insert PDF (you can also choose to import from Word or an image, or add a blank page to make the document print correctly double-sided or with two pages per sheet).

How the creator of a PDF file sets up her document determines the extent to which you can use Acrobat Reader's commenting tools to mark the file with notes about its content.

How to Convert iWork Pages Document to a PDF. Apple iWork Pages saves your word processing documents or page layouts in its proprietary format by default. If you need to make a Pages document ...

Learn how to remove blank pages from PDF files using Delete PDF Pages by Smallpdf, a web-based tool that allows removing blank PDF pages for free.

You can insert a PDF into Word via the File, Open menu, which turns the PDF into an editable document, or as a non-editable image.