If your word file already has the table of contents and you have changed the page numbers or the headers, you can update the table of contents. However, if you do not like the style, you would have to change the table of contents style.
Step 1: Click the Table of Contents to show the update bar on the top;
Step 2: Click the "Built-in" button in front of the "Update Table" button;
Step 3: Select one of the built-in styles or make your manual table of content.