Auto Numbering
Open the Customization Window
In the numbering drop-down list, select 自定义编号.

Custom Numbering
Customize
Customize Level 1 Numbering Format
Set the level to 1, change the numbering format to ①、, select the numbering style 一,二,三,…, link the level to the style 标题1, choose 空格 after the number, and modify the rest as needed.

Level 1 Numbering
Customize Level 2 Numbering Style
Similarly, note that you need to change the numbering format to ①.②, select the numbering style 1,2,3,…, and check 正规形式编号.

Level 2 Numbering
Customize Level 3 Numbering Style
Same as level 2, note that you need to change the numbering format to ①.②.③.

Level 3 Numbering
Application
Generally, you only need to set up three levels of numbering. After clicking OK, select the text and switch to 标题1 in the Home menu to set the text as a level 1 heading. The same applies to the rest.

Application
Table of Contents
Select the appropriate table of contents under the References menu.

Table of Contents