At the end of the last line of the first page, insert-separator-next page, double-click the header of the second page, and find the' Connect to Previous Page' button in the pop-up header and footer setting box.

Click to make it pop up (gray) and go to the home page. Click on the title, and there is a column "AA" in the upper left corner. Click on the triangle at the bottom next to it, and many styles will appear. Drag the scroll bar next to it to find "Clear Format" and click it, so that the horizontal line in the header of the first page is gone, and the other pages are still there!