An InDesign document can only have one chapter, and these chapters are typically combined in an InDesign book. To insert a chapter number, create a text frame where you want the chapter number to appear on either a document or master page. Click on the "Type" menu, then "Text Variables," "Insert Text Variable" and then "Chapter Number." Update the chapter number if necessary to keep your chapter numbers consecutive by clicking on "Numbering & Section Options" in the Layout menu.

A best practice that we recommend to our clients is to create a base/folio master –with styled and positioned footers and current page number special characters– on which all other masters are based. This allows a footer that may contain date or issue information to be updated once and the changes are reflected in all of the master pages. If your masters only have current page number special characters then you can just add them to each master and the page numbers will be reflected when each master is applied to your document pages.
Numbering and Section options are available in the Pages Panel menu. These options allow you to define what page starts a section and how it should be numbered. A Current Page Number marker must be set on pages in order to use this feature. The Current Page Number is a special character inserted in a text frame on a page or master page (recommended) where the page number will appear, by selecting Type>Insert Special Character>Markers>Current Page Number.
You can insert page numbers on the current page, all pages, all odd pages, or all even pages. When you insert page numbers on multiple pages, a new master layer is automatically created, and the page number is placed on it. The master layer can be an all-page master layer, an odd-page master layer, or an even-page master layer. For more information about master layers, see Creating layers.
Suppose you’ve made some changes to the styles or swatches in your chapter 5 document, and now you want to use those updated styles or swatches throughout your book. Click in the column to the left of chapter 5 to set chapter 5 as your book’s style source. Select all the other documents that you want to synchronize to chapter 5 by pressing Ctrl/Cmd and clicking the documents (they’ll turn blue when selected).
There are lots of options. For instance, you might reduce the amount of space between the number and the text by changing the Text indent at setting. Or, you might center the heading by choosing Center from the Number alignment dropdown. For even more options, click More to expose several more settings. You could use the Apply changes to option when setting level 1 to the I, II, III numbering style instead of changing it for each level.

InDesign’s automatic page numbers work well enough, but what about special cases? Some documents require pages to be omitted from total page counts. Other documents use several different systems. Sometimes section numbers or special codes must be included. Well, don’t start typing in those numbers manually, because InDesign can handle it—and quite gracefully, too.

This chapter (web page) takes you through how numbering is supposed to work in Word and the various controls. It is useful, but primarily on SEQ fields and simple numbered lists and also as reference showing the menus, dialogs and controls and going through the concepts for outline numbering. To actually set up outline numbering that works, refer to the Kelly and McGhie articles.