Folder share issue involving network path

Yes, I see this:

Just to confirm, that is not the Documents folder under USER\USERNAME right?

It's the same folder. Here's the corresponding General tab:

You cannot share that folder without opening it up to every user on the laptop. So any user besides you on the laptop would have access to your Documents.

Actually you can share that folder, but like I said it will open the folder for every user that accesses the laptop, even a guest user. If you want to proceed with that, let me know.

I'm the only user on the laptop. It's the different look from other computers that's got me wondering if this is the problem.
My wife's laptop is an identical model to mine. Here's the Documents folder properties > sharing tab on hers:



I actually do want to share the Documents folder here at home though. I often drag files between them for my work.
But the problem is here that I can't share any folders at all right now. Not even that one directly on the root of the C:\ drive

Just saw your other reply in the meantime, and yes, I'm fine with every user having access as long as it's on a private network. (not public)

Ok, open the properties of the folder, go to the Security tab. Click on the Edit button. Click the Add button and do like you did with the sharing. Give everyone access. Then once you are done save that. Then make sure all the sharing is done the same and it should work.

Yes but that's where it doesn't work.
This is the security tab currently:



But nothing can access this laptop. Something somewhere just isn't working the way it should
Edit: posted the wrong image before, but can't seem to remove it.

As explained in post 2 the share is only one part the NTFS permissions must also be set or you wont get in

That is the sharing permissions. You have to do this on the Security tab.