When searching for background historical information, stick to searching for events or specific people rather than a year or decade. How authors have designated it can make it difficult to search: 50s, Fifties, 1950s, etc. You're better off searching something like post-war era, or Cold War.
Background research is an important step in choosing and narrowing a topic. Doing a simple Google search is one way to get started, but the library also has a few encyclopedia type databases that will give you a basic overview of your topic.
The library catalog contains records for where to find all of the materials we physically own in the library: books, movies, board games, etc. It also contains links to all the e-books and streaming documentaries we own. We share this catalog with libraries around the world which allows us to get print items we don't own from other libraries, but this doesn't apply to e-books.
If you found an E-book - Just click on the "access online" button from the catalog. If you are unsure how to get to the full text check out this guide.
If you found a print book - First check to see if it is available. To locate it in the library you will need to know both the collection and the call number.