You can create your chapter numbers with SEQ fields. For example, you can use:

{ SEQ Chapter }

To insert the field, you can press Ctrl+F9; Word adds the field delimiters, { }, and you can then type in the code shown above. Press F9 to update.

You can use copy and paste when you want to duplicate the field, but note that in doing that you will have to force an update, either by selecting the text and pressing F9 or by switching to Print Preview and exit Print Preview (Ctrl+F2 followed by ESC does the trick).

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional