Start off with a four-line heading in the upper left corner (but not inside the margin) of your first page, including:
Inside the margin/header, in the upper right corner, you'll include your last name and page number.
Official MLA style does not include a title page. However, some instructors may like having one. If you have any doubts, check with your professor to find out what they want and, if they do want a title page, what kind of information they want on it.
Now, you'll start writing whatever it is you're supposed to address, which will depend on your professor's specifications for the assignment.
Always include in-text citations whenever you're doing a research paper, as close to the referenced information as you can get it (typically at the end of the same sentence). Refer to the page in this guide about In-Text Citations for more information and examples.