Believe it or not, you already know how to write a college paper. Consider the five-paragraph essay. It is as basic as a writing assignment can get. That is why you learned it back in the fifth grade. In spite of its basic nature, it is the core of most writing, no matter how complex. In fact, if you go on to graduate school and write a dissertation that is five hundred pages long it will be, in essence, the same thing. It will just have a lot more paragraphs. No matter how long the paper you have to write, you are going to have an intro, some topic paragraphs, and a conclusion.
The first step at the undergraduate level is to form a research question. Your entire paper should be focused on answering the question. Each topical section should contain the premise, evidence, and the answer to that part of the research question. It will be more than one paragraph.
Your thesis statement is built around your research question but often it is better to develop the thesis AFTER you have written the entire paper. Only when the paper is done will you have made the choices of what topics to include, how deeply to explore them, and identified what conclusions can be reached.