Hello,
Sorry for the late reply as weekend.
Actually, MS Word document is flow document and does not contain any information about its layout into lines and pages. Technically, there is no "page" concept.
In our internal code, we count page numbers by calculating content in the document. It will be very complex to calculate the height of every element accurately, it depends on lots of things, such as the used font and where/how the paragraph content breaks. We are very sorry that our Spire.Doc currently does not have an API that allows you to determine where page starts or ends.
To achieve your requirement, a better way is to manually add some markers (such as page break, section break, etc.) to the end of the page, and then get the page content based on the markers and save it to a new document. You could refer to the following tutorials to split pages by page breaks and section breaks.
https://www.e-iceblue.com/Tutorials/Spi ... -in-C.htmlhttps://www.e-iceblue.com/Tutorials/Spi ... -in-C.htmlSincerely,
Rachel
E-iceblue support team