Thank you for your reply.  It reassured me that I was on the right path. From having read other Help texts, I guessed that I would have to use good ole mail-merge and set up a numbers list in Excel. Luckily my knowledge of Excel was good enough to know about the drag&drop for sequential immediate numbering. When it came to the crunch, it was this particular type of mail merge which gave me a bit of initial difficulty. Despite my having used it happily and often in Word, for labels in Publisher, it was - not surprisingly - different in certain respects; principally the crucial point of the Print stage, which necessitated finding the option Publications & Paper Settings, and selecting 2 specific parameters, namely (1) Multiple pages per sheet,  (2) Single-sided printing (my default double printing had appeared). Once I'd sussed this, it was plain sailing.  Thanks again.
InDesign allows you to add a page number marker to a master page within the document. The master page functions as a template for every page it's applied to, so the consecutive page numbers appear on every page. InDesign updates the page number automatically as you insert, delete and move pages. To add a page number marker to a master page, create a text box on the master page by going to the Type menu and choosing "Insert Special Character," "Markers" and then "Current Page Number."
Now, modify the Paragraph settings of every Heading style so that the Left Indent is 0, and the Special indent is set to (none). Do this even if you want your headings to be indented from the left margin, and even if you want a hanging indent. Why? Because for outline-numbered styles, we will set the paragraph indent and the hanging indents (if any) when we set up the numbering.
A multi-level list is a list that describes hierarchical relationships between the list paragraphs. These lists are also called outline lists because they resemble outlines. The list’s numbering scheme (as well as indentations) show rank as well as how items are subordinate to one another. You can tell where each paragraph fits in the list with respect to the paragraphs before and after it. You can include up to nine levels in a multi-level list.

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.
The values for Number position (here called Aligned at), Text indent and Follow number with are in the Position section at the bottom. With multi-level numbering, you also have easy access to settings that control the type of numbering at each level, the characters before and after each level’s numbers (period versus parenthesis), and the list number style (1, a, I, etc.).
In a legal document, it's rare for every paragraph in the document to be numbered. Usually, you change between numbered paragraphs and non-numbered (plain) paragraphs of text. When Word sees you switching between these types of formats, it usually tries to help by restarting your numbered list back at "1" (or the first value of your list, such as "A"). There are a few different ways to make the number follow the last number of your paragraphs. In Word, this is called Continue from Previous List.
InDesign allows you to add a page number marker to a master page within the document. The master page functions as a template for every page it's applied to, so the consecutive page numbers appear on every page. InDesign updates the page number automatically as you insert, delete and move pages. To add a page number marker to a master page, create a text box on the master page by going to the Type menu and choosing "Insert Special Character," "Markers" and then "Current Page Number."
Word automatically formats text as a numbered list when you when you type a number and a period followed by a space: Word adds a tab and creates a ¼-inch hanging indent. (If the paragraphs already have hanging indents, the original settings are preserved.) The quickest way to create a custom numbered list is to change the formatting of an existing (or automatically created) list.

You can control whether your next paragraph number continues the current sequence or starts again at 1 within that same right-click menu. If one of your numbers gets out of sequence, simply right-click and choose Continue Numbering. If you want to force the number back to the beginning (say, you’re switching from interrogatories to requests for production), choose Set Numbering Value (which will also give you the option of continuing the previous list).
If you start to type in what appears to be a numbered list, Word formats your manually typed "numbers" to an automatic numbered list. The main benefit of this option is that you do not need to click any button to start numbering and you can choose your numbering style as well. For example, if you type "(a) some text" and press Enter, it starts numbering using the "(a)" format.

Changing the numbering display affects how pages are indicated in the InDesign document, as in the Pages panel and in the page box at the bottom of a document window. The numbering display also affects how you specify page ranges when printing and exporting the document. However, the numbering display does not change the appearance of page numbers on document pages. numbering in indesign
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