The first step to any research project is selecting your topic. This can be challenging, especially if your assignment is very broadly defined.
One way to narrow down your research options is to use reference works (subject encyclopedias, bibliographic essays, even Wikipedia), to get your bearings. These overviews of a subject area can give you the big picture, and perhaps generate questions you want to explore in more detail. Some call this "presearch" since it happens before actual research begins. We all know to use Wikipedia cautiously; just remember to read critically and consider the sources of information you find there.
Subject encyclopedias are the great reference sources since they are written by recognized experts in the field, contain citations or suggestions for further reading, and sometimes introduce you to the significant debates and controversies on your topic.