Using the Same Webpage in Multiple Websites
A static page is created and made accessible in the current website. Later you can copy it to different other websites from Website >Configuration > Pages. To do, leave the Website field vacant.
On the off chance that you need to duplicate/copy it in one other website, duplicate the page and set the new site.
However, upon editing the page again, the end user can see that the change only affects the current website. A new page is duplicated and tied up to the website. The original page still being linked to all websites.