Registry edit key deleted

I was trying to save my new games to my d drive and i went to registry edit hkey to do that and i only typed in d. For example there was things that said c:systemfiles:/ and i changed it to d. I did that for every one. Ever since i cannot do anything, i cannot open command prompt as an administrator, cannot open registry edit, cannot system restore or reset the pc in settings as well. every time i try to do these things my pc says it needs to restart or it says its not responding. I have an expensive gaming laptop and was trying to get my second drive into gear and messed up. What do i do from here?