So I’m assuming you’ve downloaded the CS language files linked to here? It’s technically not a program- it’s just the files that enable your computer to run a ChoiceScript game.
I would highly recommend downloading ChoiceScript IDE, a program which was designed to be a space for you to edit/write ChoiceScript code while having testing options in the same window instead of having to constantly upload files to your browser. It also sets up new game folders with most of the relevant files necessary so you don’t have to think about it too hard.
If you don’t want to do that yet and just want to see something work, navigate to the ‘web’ folder under the dfabulghjkdhkjhdfjgjkdfgh-blahblah folders that you’ve just downloaded. There should be a folder in web called mygame. Open that, double click index.html, and it will open a browser window on your default browser and run you through a testing game. (You may have to upload a folder to the browser window that opened, but it’ll tell you which ones.)
You can modify that test game, as well as see what kinds of files you’re going to need in whatever game you eventually write, by opening the files in the nested scenes folder and editing them with a plaintext program that most computers have, like Notepad.
I found this tutorial very helpful in establishing my basic knowledge of what bits and pieces I need to write code that eventually turns into a game.