For all of your bibliographic needs for your research paper and secondary sources use this website from the Chicago Manual of Style Online. It will provide you with various examples from citing a book to a thesis.
When it comes to citing primary documents, which are the documents you will be using for your Archives paper, the Library of Congress has provided various examples of how to cite materials here.
Given that we are limited to in-person help, I thought providing you with an example of how to complete this task with digital materials. The Library of Congress lays this out very well with the following way to organize a citation:
While this might feel tedious, one place that helps you find all this information will be at the end of the digital document. It may have the subtitle of "Dublin Core", "Metadata", or "Library of Congress" as a way to spot where you can find information about your document to use it for a citation. For my example, I used this Proceedings of the Second Annual Convention of the Colored Citizens of the State of California, 1856 for the citation below: