Pay close attention to the server name and domain name. This is the publisher and it will help reveal who is sponsoring (or hosting) the site. Here are example domains:
.gov (US government)
.net (internet resource)
Generally - but not always - .edu and .gov domains offer more credible information because they're generally well-established and well-funded organizations that are staffed by professionals and/or experts. However, as with all sources, remain skeptical. Bias and misinformation can be present in .edu, .gov, and .org sites, just as in others.
These websites look authoratative, but, upon closer inspection, they're not.
Still not finding what you need? One of the key things to know is that, particularly with scholarly material, not everything is freely available online.
Sometimes the perfect article is only available in print. Or requires a subscription to access through an academic journal. The library likely has access through their subscriptions, which you pay for with your student fees. Librarians can help you figure out how to get what you need.
Google Scholar provides a simple way to broadly search for scholarly literature - in Google, per se. From one place, you can search across many disciplines and sources: articles, theses, books, abstracts and court opinions, from academic publishers, professional societies, online repositories, universities and other web sites. There is a free version - and an SHSU subscription version. As you can guess, you get more with the subscription.
There are a multitude of acronyms and tricks to evaluating sources. Use the method preferred by your instructor, knowing that the important component is to develop a habit or pattern you can use when evaluating all information.