I need Roman numerals in the footer for the first nine pages of the document, then to start with Arabic numerals starting at number 1 for the remaining 48 pages
You will find the WRITER GUIDE very useful here Writer Guides | LibreOffice Documentation - Your documentation for LibreOffice You can download a PDF of if you do a lot of writing it is worth buying a printed copy from LULU.
Chapter 5 FORMATTING PAGES: BASICS has a section on Numbering Pages, and answers some of the questions you have.
Thanks very much for these most helpful answers. I now know what I need to do, but I’m still battling with it!
My main difficulty is creating a custom page style.
Header and footer are properties of page styles. A page style defines the general appearance of a set of pages (margins, header, footer, columns and others). Each page style tells how to format page numbers in the pages it controls. Consequently, you need to define one page style for the pages with Roman numerals and another one for the pages with ordinary numerals (for me, “Arabic numerals” is ambiguous because the glyphs are different in Arabic). Perhaps you need also a different page style for the cover (unnumbered) and others for specific parts of your document.
Read the Writer guide thanks to the link provided by @pertermau to see what you can require from page styles.
Once you have designed your styles, you need to switch from one to another when you enter a new part of your document. This can be done in various ways, more or less automated. As you are beginning to use Writer, I suggest the manual method.
A change of page style can only be done with a break. Insert>``More breaks>Manual Break` will allow you to choose which page style to activate after the break and to reset the page number.
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