Determining what kind of source you're dealing with can be challenging, but all fields of research use multiple types. Here are some basic definitions to help you better understand the differences. Also each page of this guide provides some examples available to you for your research.
Most databases include an option to copy and paste pre-made citations for scholarly journal articles. Always double check them against the citation style guide to be sure that there are no mistakes (they happen).
I'm also available to answer questions about specific citations. Citing primary sources can be particularly tricky.