Biography in Context, our biggest biography database, contains many different types of articles. Magazine or encyclopedia articles may be more popular in nature, and are often easier to understand. Is your professor asking for more scholarly material? Then you might want to "limit" your searches to scholarly (or academic) journals.
Make sure you understand the requirements of your assignment. If you're not sure, ask your professor!
When searching for information about a person,
Do a "people" search in Academic Search Complete.
Do a "person" search in Research Library (Proquest).