Do any of the following:
Set top, bottom, inside, and outside margins: Click the arrows or enter values in the fields under Document Margins. The inside margin is the edge of any page that goes into the binding. The outside margin is on the outside edge of each page.
Use different headers and footers for left- and right-facing pages: Click toolbar.
Note: If the Document Body checkbox halfway down the sidebar is selected, this is a page layout documents, you set header and footer margins, not page margins. The inside margin is the edge of any page that goes into the binding. The outside margin is on the outside edge of each page.
Use different headers and footers for left- and right-facing pages: Select the “Left and right pages are different” checkbox below the Facing Pages checkbox.
To learn how to edit headers and footers, see Add page numbers in Pages on MacAdd and remove headers and footers in Pages on Mac