2. The "Style Format" column appears, in which the titles 1, 2 and 3 are mainly used. Title 1, title 2 and title 3 are applied to the titles of all chapters in the main text respectively. Attributes of title 1, title 2 and title 3 (such as font size, center, bold, etc. ) you can modify it yourself. Modification method: right-click "Title 1" and select "Modify" to open a menu of modification, which you can modify according to your own requirements.

4. Don't use the title 1, 2, 3 to define each chapter in the text. It is very convenient to define, just point the cursor to "Chapter 1 Introduction to Refrigeration" and click the title 1 on the right with the left mouse button. Similarly, define1.1with headings 2 and 3; 1. 1. 1; By analogy, the second and third chapters are also defined in this way until the end of the full text.

When everything is defined, we can generate the directory. Move the cursor to the blank position where you want to insert the table of contents at the beginning of the article, select [Insert]-[Citation]-[Index and Table of Contents], select the second tab [Table of Contents], and then click OK at the bottom right. It doesn't matter.

6. When modifying the content of the article again, you need to update the table of contents. Method: Right-click in the directory area and select Update Domain. After selecting Update Domain, the box shown in the above figure will appear. Click the second "Update entire directory" to confirm. It doesn't matter.

In fact, everything you can find online is in Baidu, with illustrations, and you are very eager to learn.