It is the same process. If you want an automatic table of contents, one you can update, you need to change the source material to change what is in the TOC. You cannot simply alter the TOC directly and have those alterations survive an update.

Controlling what goes into the TOC

To add something either add something in a referenced style or add a TC field, Ta delete something, make sure that it is not in a referenced style or in a TC field. Please read the article.