If you want to create subpages on your website first of all you will need to have or create a page that will serve as the section where you will add the subpages. Once you have your section page created, please follow these instructions:
Go to Content > Pages
On the Primary menu, find the page that will serve as the title of this section and click on the blue arrow to “Add New Subpage”
Choose your preferred Layout page and click on Create.
Repeat the same process for every page you wish to add under this section of your website.