It doesn't seem that I can open any of the doors. I was still able to get to the "prison room", but got stuck after the O2 room. I stopped after I got softlocked because the ladder down from Middle Room 1 cannot be escaped.
The vague notion of a "casual room" that just has reverse gravity was really funny to me. There's also a bug in that room where you can jump infinitely from time to time but that was also mostly just fun. The character design is also pretty amusing. There's some good ideas here.
I recommend that you keep making small games to get more familiarity with Unity 6. It's clear this game was made at a very introductory level. There's nothing wrong with that necessarily, but it also seems like the team wanted to do more and do better. Thank you for making this!