Unfortunately I'm not a game developer, I'm a writer, so I can't give you any meaningful critique when it comes to how to fix gameplay issues, but once you do that I'm sure the game will be a lot more fun!
One of my biggest issues outside of glitchy gameplay was the lack of variation, maybe make the key placements a bit more challenging. I'd also say that it might be more fun to organically give the player hints, rather than having it pop up at the bottom after a given amount of time. Maybe something like a journal the player can check, giving the story a bit of narration alongside hints of where the key is. Idk how complex that would be though because I don't develop games lolz - just some food for thought!
I think overall this is definitely a good structure for a game, but missing some elements that would really make it pop, I think it's just stuff that comes with growing as a developer maybe. Good luck on your journey ☺!!!