Question: What does which template do?

[flow7]

I'm a beginner, customizing my own theme, using Devtools and Theme Inheritance.
Question(s):

• how do I know which part of my site was generated by which template file? Or - which template is responsible for what?
• is there a good overview somewhere that makes navigating templates a little easier? Or is there a development tool I'm missing?

As a beginner I still find it confusing to navigate through the various folders, files and the code to understand where what comes from - any help is greatly appreciated!!! Thanks