Beginner questions

Hi everyone,

I’m just starting and one thing that confuses me is that every project I open has several folders inside for organization purposes, and that’s fine.

1- Is there a rule that most artists use on were is the main scene to open? For example in the Automotive beach scene I get this but I don’t know what file to open to see the final shot.

2-For example for the Automotive beach scene and even for Automotive material pack, why must I add them to a scene? Why can I open the scenes as they were made?