How to add numbered headings in Pages?

I found a previous similar question, so to clarify: I don't mean a list, I don't mean headers and footers. I mean Headings as in Chapter Titles.

This is a paper / book / whatever

1. Introduction

lots of text

1.1 some sub-heading

lots of text

2 Management Summary

2.1 blalba

2.2 blabla

3 New Chapter

Is there a way to do that? Pages version 12.0

Thank you.

Yuan-Yuan