You can also click "Content" from the Drupal admin menu. Just look for the page you want to edit in the pages listed (don't forget the filter option if you know the content type).
Delete an existing page
To delete an existing page, click "Content" from the black menu bar. See image below:
Then click "Edit" next to the page you want to delete. See image below:
Once you are in the "edit" mode, scroll all the way to the bottom of the page and click the "delete" button. See image below:
Now the page is deleted.
Add a New a Page
To add a new page, click "Add Content" from the Drupal menu. See Image below: