In File Explorer open the Users folder on your c:-drive. Every folder on the right is a user account and then there is Default and Public.
Or go into Command Prompt and open the User accounts app. That only shows real users.
In Windows 10 there are 2 kinds of accounts: a local account (you login with just a name) and a cloud account connected to Microsoft servers (you login with a Microsoft account, an email address). Maybe by accident you made both?
Finally, we recommend having 2 administrator accounts on a PC. One for normal use and one for emergencies if the normal one is getting corrupted.
I got a message from Microsoft (?) stating my computer was attempted to be signed in from an unknown area - (I get a lot of this 'this is a new computer do not recognize it") and it advised that I change my password - so I did and for 2 days I would sign in with the new password then all of a sudden it reverted back to my original password - well today when I open my computer I have two names in the bottom left corner one my original sign-in name and the other is my email address - how do I investigate that or find out how many user accounts I have - I live alone and should only have one - me

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