I tried control s, save, save as, and none seem to work. For the ctrl s and save it stops at “saving”, and save as doesn’t work. I want to try and open a different window but I’m afraid it will close the first one, deleting all my progress. - YouTube
Open your folder where is located your game.json, make a manual copy for backup somewhere else on your PC.
After go in preferences, enable autosave, launch a preview (launching a preview save the project in autosave) and close GDevelop.
Launch again GDevelop and look if the autosave works.
If not you have always your backup.