Ok, that’s fine if you see some code example and how it runs. That’s the CSIDE editor.
As for that zip file, it should have included a lot more files than mygamegenerator.js (which is not used by us, only by the engine itself)
From there go into web/mygame/scenes/, that’s where the CS example code are stored, which you can look at to learn from, or safely ignore.
When using CSIDE, your CS code files can be stored anywhere, not necessary to be inside that web/mygame/scenes directory. Every project just want a startup.txt and choicescript_stats.txt to start with. For a small project everything can be written in just these two files. For larger projects it would make sense to divide up the rest of the story into chapters. But this is getting ahead of ourselves. Try a very simple/short story and see how the basics work. 