Could you make an explanatory video for the template builder?
My blog post below covers the template builder usage completely. Suggest reading it carefully as it also covers using a Bootstrap 4 3rd party theme builder usecase for even more control.
www.joomlapolis.com/blog/kyle/18797-template-builder
What are its advantages?
You can change the Bootstrap 4 colors so it better blends in with your Joomla template.
I have the stock template, then I have about 100 lines of overrides (including color etc...). Will it be easier to create a new template with it?
Depends on what you're changing.
What are those red, green etc... colors for?
As stated on the Theme tab they're Bootstrap 4 color variables.
How can I change the colour of my fields with template builder?
No idea what fields you're trying to change. The Template Builder is to allow you to build custom Bootstrap 4 and Template CSS based off your Theme. It then generates and installs a CB template plugin automatically. It is not for implementing custom CSS outside of that scope, but it does also provide easy access to Overrides usage too using the Overrides tab.
krileon
