Identifying topic, text and author to research on

After I have completed my thesis statement now I have to start writing a research paper. I have been told that writing a research paper would be more challenging compare to writing a position paper. A research paper requires me to do research more than the citation of authorities. I am required to collect and interpret evidence and also include the opinions of early investigators. If that the case, what I need to do is to put all my effort in order to complete my research paper because I must have references and I must also cite my sources.