Proper Numbering of Research Paper

Hello I am writting a scientific research paper and have a question concering the prober numbering.

I have the following topics

Table of Contents
Preface
- Decision of Topic
- Acknowledgment
Introduction
- Description of Topic
- Goal of the Paper
- Scope
- ...
Main Part Baiscally consist of all my research and testing, after the conclusion I have still some further points such as
- Further Defining of Topic criticsm, comparing etc
- ...
- Conclusion
- Fruther points

Glossary
Attachement
Progress/ Milestones of writing the paper
Sources

My question is, do I number:

1 Table of Contents
2 Preface
2.1 Decision
2.2 Acknowledgment
3 Introduction
3.1 Description
3.2 ...
4 Main Part Here I first see a problem, what kind of titel is "Main Part" also that would only give me
4.1 ... second degree headings for al my research!
But how do I make the transition from "Introduction" to the "Main Part"?

How to number the rest? How to introduce the conclusion, attachement etc?
Do I number the introduction and preface?

Thanks ever so much!!