Before you use a search engine, it’s good to have brief understanding of how one works.
Search engines look at all of the available web pages that exist, which is similar to a librarian finding all the books in a library.
The search engines would then look at the page content of each page, which would be alike to a librarian reading all the books in a library.
Then the search engine can use that information to recommend the right page for you, which is similar to having the librarian find you the right book.