Note, the icon for the Clangen.exe file looks very similar to the files next to it. Just search ".exe" with the Clangen folder open, and run the "Clangen.exe" file. If you don't want to have to keep opening the file every time you want to play the game, make a shortcut to the game.
If you are absolutely sure that the Clangen.exe program is not in the file then something is wrong and you should probably either redownload the file or take up your problem in the discord. Hope this helps :)