Some students get confused by literature review assignments and turn in work that is more like a research paper than a literature review. Here's how one professor explains the difference: "In a literature review, the focus is on what researchers in the field had to say. The articles themselves will be referred to specifically. For a research paper, the articles are used to support the conclusions that you reached, rather than to directly discuss the articles themselves."
First, read the relevant section in the style manual you are using. Follow the directions your professor gives you. If your professor uses a rubric, study the rubric.
The University of North Carolina's Writing Center has helpful information.