I have searched the Help section but cannot find how to make a page number entered on the first page continue to all following pages in a 1-2-3- manner.
Edit the page properties > ‘Format’ > ‘Page’ and switch on ‘Header’ and/or ‘Footer’ and set the details as needed. Suppose you are using a footer and the same footer on all pages. The ‘Filed’ ‘Page Number’ entered into the footer paragraph will do the trick.
You may want to read about “Creating headers and footers”, “Formatting headers and footers”, and “Numbering pages” in the complete Writer Guide downloadable from this location e.g. A continuous guide often is preferable over the short help texts. (Nothing substantially changed insofar since V4.2.)