infinite loop

I just transferred data from my old MacBook Pro to my new 2020 MacBook Air.

I have the following curious problem. In the System Preferences/ Users & Groups

I see only myself and a Guest User. No problem.

However, if I “Go” to “Computer” and then click on “Macintosh HD” and then click

on “Users”, I see four accounts:  my own account, a Shared account, a Deleted Users account

and a greyed out account with the name of an account that used to be  

on my old MacBook Pro with a “4” attached to it. Let’s call it “Laura 4”.

Clicking on it has no effect.

If use Terminal and  do “cd ..”, I can see the “Laura 4”  account and enter it.

“ls” shows a bunch of folders, one of which is “Users”. I enter it.

There is one visible folder “Deleted Users”. I enter it.  Surprise:  there is “Laura 4” again.

And I can keep on going in this infinite loop.

A related problem may be the fact that I only transferred 120 or so GB to the computer, but storage says that the computer is almost full. 20GB free space.  My stuff is nicely colored and the rest of the bar is grey.

What can I do about this?