Peer review is a process that journals use to ensure the articles they publish represent the best scholarship currently available. When an article is submitted to a peer reviewed journal, the editors send it out to other scholars in the same field (the author's peers) to get their opinion on the quality of the scholarship, its relevance to the field, and its appropriateness for the journal.
All peer reviewed articles are scholarly articles. However, not all scholarly articles go through a peer review process. You may need to clarify with your instructor about whether or not they are requiring you to use only peer reviewed articles.
Guess what?!? You don't have to read a scholarly article from start to finish. In fact, you shouldn't even attempt it at the start. Skipping around to certain sections and knowing what you'll find in those sections makes understanding the article much easier.
The following video gives you one strategy for dealing with journal articles that have very clearly defined sections (abstract, methods, discussion, results, etc.)