Alright, it's okay thanks at least for trying to help me :3
Viewing post in You do not have permission to open the application “Backrooms”.
i can solve your problem :0. all you need to do is install the itch.io app and it'll give you access to any game. This solved my problems with opening several other games. I hope it helps. if you have any more questions, please feel free to ask. I'd certainly walk you through if you need any more help