The topic's title as displayed in the table of contents can be changed using one of the following ways:

  • Right click on the topic and select "Rename"
  • Select the topic then hit the "F2" keyboard shortcut
  • Select the topic then go to the "Home" tab then click the "Rename" button in the "Table of contents" section

See the How to rename a topic in HelpNDoc step-by-step guide