Here are two ways to create a new page in a desired space.
1.
-Click "Create" and select "Blank Page" to create your first page.
-New pages are created as children of the page you are currently viewing.
-Give it a title and click publish
2.
-Click on the three dots next to create
-Choose blank page to create a blank page
-Use the drop down to choose the space you want to create the page in.
Tips.
You cant edit or add content to your page until you have given your page a title and clicked publish.