Cannot uninstall and re-install UE4

They were before I “fixed it” and could get it to uninstall and install again.
Then when I re-opened, the level was dark. There was nothing but a sunlight actor, which wasn’t on for some reason. When I pressed unlit, it didnt do anything.
Its like the universe I did died completely.
then I went to other projects and they werent there anymore, even if you can see their photo under my projects labels