Footnotes or endnotes, similar to comments, provide you more information about something in your document. Footnotes appear at the bottom of the page, while the EndNotes appear at the end of the whole document. Please see below to add a footnote.
Step 1: Move the cursor to the end of the term or paragraph that you want to add a footnote;
Step 2: Click the "References" tab from the ribbon;
Step 3: Click "Insert Footnote" in the "Footnotes" area;
Step 4: Type in the notes for the selected term or paragraph.
Step 5: If you need the notes to display at the end of the whole, you need to click "Insert endnote" in step 3, and then type the notes at the end of the document.