This acronym will help you evaluate the credibility and reliability of a source you are thinking of you using.
The CRAAP test was developed by librarians at CSU Chico. Link to the original test and a set of questions that will help with the evaluation.
You can think of peer review as a "stamp of approval" from academic experts. When an article is published in a peer-reviewed journal, you'll know that experts in the relevant field have read the article and, independent of their own particular opinions, verified it to meet a high standard of scholarship. Peer reviewed journals are occasionally also called scholarly or refereed journals depending on the publisher.
Almost all library databases including Primo have a box or a tab that allows you to limit your search results to peer reviewed articles.