How to delete spurious Windows account?

Yes, I am back to pester this forum, sorry. A few days ago, as I was doing something or another, I must have pressed an undesired link, as to my dismay, Windows was creating a new user account. When that finished, I found myself in what I can only call a spurious account, given that, for example, there was no Windows button, the screen was not at all the usual one, and so forth.

I was trying to figure out how to get out of this and return to my user account, so I tried Log Out or Sign Out; which ever one it was, I was back to the desk top, with at the lower left corner, my two accounts were listed. Now I want to delete the John Liebson account and keep my John account. Given the very odd format of the John Liebson account,I wonder if this nifty code provided in my long "I can not remove my old Administrator account " discussion here, provided by a very patient and knowledgeable user:

net user Administrator /active:no

I have looked at Accounts in Settings, and find nothing about the John Liebson account.

I am not even sure how to enter this, and I guess I can only hope that it works as well as it did for a legitimate account on my wife's computer and does no damage to my account. I await whatever responses I might receive for this quest for help. For anyone who sees this message and has not read anything from me previously, a brief statement that I am not at all fluent in all the many codes, etc. in Windows, such as the code above. I use the computer for such obscure tasks as creating a massive fire service training course, which has 126 35mm slides in it, the state of the art at the time.