If you need to find out more about a specific journal
Looking at the publication record in a database and the publisher's web site are two places to start.
By clicking on the publication title in an article record in a database, it will tell you if the journal is scholarly and/or peer reviewed. It may also give you a link to the publisher to find out more. For example, the image below shows publication details for Nursing Standard which includes the information that the journal is a scholarly journal and peer reviewed.
This process may look different in other databases, but the concept is the same. Look for the title of the journal in the article record, then click it to get more information.
Library databases will not always provide all the information you need about a journal, but there are other ways to find information about journals' publishing practices.