In Atticus, page numbers in the PDF (Print) version are automatically generated based on the layout you've selected in the Headers and Footers section of your theme.
If you click the preview icon at the bottom of the Right Sidebar, you can open a previewer in the Writing Tab. The previewer defaults to iPad, but you can select Print from the dropdown menu above the preview.
You can scroll through the pages and it'll show you the page numbers there.
Note: if your page number is set to appear in the header, it will not be displayed on the first page of any chapter or special page. This is because the 'chapter heading' formatting takes priority on those pages.
If you’d like to change the layout of your Running Headers/Footers to adjust the placement of your page numbers, you can do this in your theme under Header/Footer.
You can make changes to your theme on the Formatting Tab by clicking the three dots next to the theme name and selecting Edit or Edit as New Theme.
For more details on how to set up or adjust your theme settings, you can refer to this tutorial: https://www.atticus.io/create-a-custom-theme/ It provides detailed instructions and tips on creating and modifying your theme.