How to Restore Pages and Functionality

I had difficulty editing pages. I deleted pages that I didn’t need, or couldn’t get to function properly. As a result, I only have the “About” page. I don’t see a prompt that will allow me to upload a theme file. I don’t have any plugins that are visible. When I got out of Edlin to get to another theme, I only get the “About” page. When I switched back to Edlin, there is only one page, the “About” page. The other features and pages have not come back.