In this article, we'll explain how to add footnotes semi-manually in Google Docs (online and mobile versions). Google Docs will either give you the number and space for the footnote, or you can insert it automatically, complete with the correct formatting (MLA, APA, or Chicago).
Insert Footnotes in Google Docs
Footnotes provide more information about a particular part of the text, such as a quotation or additional details, without cluttering the main text.
One way is through the desktop website, via the Insert menu, if you want full control over what you include in the note.
Place the cursor exactly where you want the footnote. This is where the number will appear.