I'm talking about the System 7/8/9 days of macOS. I really like the aesthetic and workflow in the older macOS versions (call me a masochist) and I'm hoping if someone knows of something that already exists. I know there are plenty of skins/themes that hearken back to Windows 95/98, but most of what you find online when you look for "Linux like macOS 9" is things that make it look like modern macOS.
I found this post, but it refers to System 6: https://hexbear.net/post/786438
I did a quick search on r/unixporn (I just put in "System N") and found several posts, mostly about System 6 and System 9. Usually they post the links to the dotfiles in the comments. Good luck.
By the way, I don't think you'll find a specific distribution or desktop for what you want. You'll have to customize several things separately, look for documentation, dotfiles, etc.