This training document gives instructions for finding the page you want to edit in the content tree of the Sitecore Content Editor.
Finding the name of a page
Finding the page in the content tree
NOTE: This is important to remember when first creating a page, as the page name directly impacts the URL structure. Changing a page name after it is created and live on the website, or changing its location in the content tree could cause visitors to the old URL to receive a 404 page not found error.