A table of contents, as the name implies, is creating content as a table. Some examples are index at the start of a book, or an appendix often seen in the beginning or ending of a book. Rich text formatting enhances the look of your Table of Contents.
To create your own table of contents in Ms Word, follow these steps:
1 - In your document, click on a heading that you want to appear in the Table of Contents. Next, apply to it a heading style that you like, e.g. ‘Heading 1’. Similarly, apply ‘Heading 2’ to the sub-heading, and so on.

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2- Choose Index and Tables from Reference in the Insert menu.
3- Click on the Table of Contents tab for options you might want use to apply any changes to your headings.
To change font options of your headings, such as size or color, go to the Table of Contents tab rather than using font change menus on the toolbar. Make sure you have chosen From Template in the Formats box. Click the Modify button, and then again in the new window, click Modify.
Ms Word displays three levels of heading in your Table of Contents, by default, but it is possible to show less or more headings. To do this, change the number in Show Levels on the Table of Contents tab.