Select the References tab in the toolbar at the top of the screen. Then click on the Table of Contents button in the Table of Contents group. Select Insert Table of Contents from the popup menu.
Next, select the formatting for the table of contents. In this example, we've selected Formal as the Format and 2 as the number of levels to display in the table of contents.
Click on the OK button.
Now when you view your document, the table of contents should appear.