There is no function built into Word that does what you want.

You will need to write a macro. That is write a macro, not record one.


"Header" or "heading?"
What is the difference between headings and headers?


I expect that you will get help with writing a macro here but you need to learn some concepts and vocabulary. Here are some starting places:

• Getting to grips with VBA basics in 15 minutes
• Instructions for Installing Macros from Forums or Websites by Graham Mayor, MVP
• VBA Code Examples (3)
• Install/Employ VBA Procedures (Macros) by Greg Maxey
• The art of defensive programming