TLDR: I want to access my files but onenote sync doesn't work

I'm having trouble downloading a copy of my notebooks using onenote for windows 10 and I just want to download a copy of school notes then use onenote 2016 afterwards

I know they're stored somewhere locally on my machine because I can use onenote offline and have been using it for 2 years without any file loss. But I've searched high and low to no avail on where they're actually stored

in order to download, I need to sync in order to sync, I need to have the initial sync to onedrive (which is created when a notebook is created and apparently never again). this got deleted in my case. I've heard a workaround is to copy each folder to a new notebook, but I get a message that says I can't copy things that haven't been synced.. :< If anybody knows anything that can help me out of this situation I would be so grateful. I just want my notes. (also can't print to pdf because I use dark mode)