After playing more, its not so dark, but a nice Darkness when you're playing in porper Lighting Conditions. Your Levels are very vast and empty, very unnatural feeling tho, I'm assuming they're placeholders for testing Purposes.
The Camera really should just be RE-like, the 3rd Person one for this doesn't work well I think. Your Players Hand-IK for the Baseball-Bat and Head are also too far behind the Playermodel, so it looks like he's bending backwards a bit all the Time.
No Idea if or how I can open my Inventory, didn't really try, it opened for the Flashlight Part by itself anyway. Inventory lagged horribly tho, are you recapturing your Rendertargets every Frame there?
The Puzzle itself was alright, the Scratches behind the Wall could and should be more detailed I think, currently they could just aswell be only in the Paint, and not through the actual Wall itself. You should also be able to investigate them from the Backside.
I liked that the Riddle wasn't straightforward, but had you go through both Sets of Numbers, and I liked that the Doors that couldn't be opened pretty much all had a unique Message. Would love for it to be shown more visually aswell tho. Generally I think you need a bit more visual clarity, to where the maintenance Room is, that a Door is locked with a Keypad etc. But again, I'm assuming its a rusty generic Door everywhere because your Levels are placeholders for testing anyway, and not final.
Overall, if you fix the Performance, and revert back to RE-Camera everywhere, it's all about replacing Placeholder UI, Levels, Models, adding more Props and more Detail, then content and missing Systems ofcourse. I didn't really think I encountered anything being buggy. Your Hitboxes for picking up Things, interacting with Doors etc. are really small tho, with the imprecise movement on Keyboard thanks to your pretty bad Camera System, it doesn't make it easy to hit those. (I couldn't try it with Gamepad, because it kept spinning and attacking constantly)
Your Combat is boring. It doesn't need to be super engaging and deep, dodgerolling and Combos or whatever would be way too much for this, but it should pose a Thread instead of just stunlocking your Enemy, so you'd prefer to avoid them I think. Maybe it'd be this Way if you encounter 2 or more at once, but currently its just annoying for them to be there, and nothing else. Another aproach could be to make them scarier, you overall have a lot of Room for Improvement on your Atmosphere.
And consider adding RE-like Door loading Screens, instead of slowly fading to black, then being stuck behind the Door with inverted Camera for a bit until you're allowed to move.