On larger sites, it is quite common to lose your spot when working on a page in the front end or back end.
The best way to find a page in the CMS is to go to Page Builder > Pages. This will show you a list of all the pages on the website.
Then, use the Search box above the pages list to search for your page. Use unique words to narrow down your results.
Your results will be listed as [Category] Page. Click on the link within the brackets  to go to the category where you page is found, or click on the Page to go to the actual page.
NOTE: The search tool only searches for words in page titles. For searches involving content within the page, use the search tool in the front end of the site.