I know this is a simple question. I just want to know how to have page numbers show at the bottom of each page of the book I am writing.
https://help.libreoffice.org/Writer/Page_Numbers
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You must first create a footer in your page. This is done in the page style. Very likely, you are using only a single page style which is Default Style. You must enable the footer in the Footer tab of the style definition. Then place the cursor in the footer to Insert>Field>Page Number. If you want to customize the position, right click on Footer paragraph style name in the styles side-pane (F11); this is much better than clicking on buttons the toolbar.
These instructions are intentionally concise to incite you to read the built-in help. You can also search through this site where the topic is covered by numerous question.
When you have done your numbering, you’ll have new questions such as unnumbered pages at beginning and end of book (covers), parts with independent numbering (e.g. TOC and indexes starting from 1 with Roman numbers), etc. The answer is dedicated page style(s) per part. Once you understand the principle, it is quite simple. Enjoy!
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