[CentOS] Lost my menu options again - KDE messes with Gnome?

> ----
> useradd -p PASSWORD -m roger
>           ^ needs a  ^
>             space    |
>                      | what are you trying to accomplish here?

The web page where I got the command said I needed it. Said it was to
create a home directory.

In any case, I tried:
useradd -p password testguy

and I still can't log in at the GUI prompt with the username "testguy"
and the password "password".

Do I have to specify to set up a Gnome interface for the user or
something like that?

Dave