I believe this has been posted elsewhere. (
https://answers.microsoft.com/en-us/...d-1bc72d1472ca)
For cross-posting etiquette, please read:
A Message to Forum Cross-Posters Excelguru Help Site - A message to forum cross posters
You would use the Define New MultiLevel List dialog. I suggest reading
How to create a table of contents in Microsoft Word by Shauna Kelly.
You would place the § Section symbol before the displayed number in that dialog.