As you do your research, keep track of your sources.
Your professor is going to want to know how you came to your conclusions in your paper, and that means citing your sources. Using lots of sources is not a sign of weakness. It's a sign of strength that you did research and thought about what you found before writing something on the topic yourself.
Scholars have developed a variety of Citation Styles to help researchers let other researches know what sources they found and how they used them in their own research. Choose one method of citation for your paper.
Librarians can help you figure out how to site an individual source if you're unsure.
Lots of the databases (and searches like OneSearch) will provide you with a citation for the source you're looking at.
Check these auto-generated citations for accuracy. Not all of them are correct. But, using them and checking them does speed up the citation creation process.