Hello,
UPDATE: phpdocx 9 added the pageNumberType option to set start and format values when creating new sections using addSection.
You can work with sections (https://www.phpdocx.com/api-documentation/layout-and-general/add-section-Word-document-with-PHP) or a custom template. Anyway, the easiest solution is generating the DOCX documents standalone (first and second pages as a document, and other DOCX with the page numbering) and then merge them using mergeDocx (https://www.phpdocx.com/api-documentation/docxutilities/merge-Word-documents-with-PHP).
Regards.