Evaluating sources is an important step of the research process. The evidence you choose to use for your research should accurately support what you are trying to argue and it should lend credibility to your work. If you cherry pick your sources, or find quotes that "kind of" fit in your paper, that can have the opposite effect.
Check out this video tutorial from Winona State University on the differences between scholarly, trade, & popular articles:
When evaluating sources of information for accuracy and credibility, there are many aspects of the source that you can consider. One source that might not fit your research question could still be useful to someone else, so it's not helpful to think about "good" or "bad" sources. Most importantly, if a resource is from a trustworthy author or organization and helps you answer your research question, then you have identified a useful source. Please contact your instructor or a librarian if you would like more help!
Check out this short video from Western University on how to read a scholarly article.
For more on the SIFT Method, check out this blog post from Mike Caulfield, Director of Blended and Networked Learning at Washington State University Vancouver: