A free papers search engine
Your friend is probably thinking of Sci-Hub. Warning: it's likely illegal, including to use the service (as opposed to uploading stuff onto it), in most jurisdictions. If it's not already illegal in your jurisdiction, the trend is towards illegality (i.e. lawsuit after lawsuit has been ruled on, and they are usually in favor of the copyright holder).
If you want to do things legally, try something like Unpaywall, or ask your local librarian. Librarians are incredibly good at finding papers, and they can often access something for free even if you can't.