You submitted the engine project file. Not an executable version (apk, exe etc.)
You have to export your game to selected platform with the export function of your engine.
Only people with construct installed can open what you submitted.
i can't find out how to do that, can you help me?
Somewhere in your engine should be a button or option to Export/Build the game.
Search how to build (or export) game in <engine name> on Google
Im done! you can download it now as a zip, if it wont work tell me.
