How to insert the "number of pages" into the templates of bibliography ?

EndNote EndNote General
1

I’m trying to show the pages (e.g. pp. 2-19) and the number of pages (e.g. 390 p.) at the same time.

but only could find the “pages” and “number of volume”.

version: EndnoteX9

2

Book ref type uses the generic field “pages” for Number of Pages, and Section field for Pages.  But usually no one cares how long a book is, if you are citing a “chapter” (book section) so that ref type doesn’t designate a field for number of pages.  You could edit the book section and use one of the unused fields for this info, if needed.