How to change/select your nickname for IRC using NickServ

Real beginner with IRC so bear with me.

NickServ appears to be some sort of external 'application' that allows you to register and sign into IRCs.

To register:

/msg nickserv register <password> <email>

To 'sign in' (identify):

/msg nickserv identify <name_password> <email>

Upon registering, I get this email:

jimboF2,

In order to complete your registration, you must send the following
command on IRC:
/msg NickServ VERIFY REGISTER jimboF2 xasdao231d

So where did jimboF2 come from and how can I change it?

Also, upon using a different irc client, it thinks my nick name is james_, the username of my Ubuntu account. I can't seem to change it to jimboF2.

07:49 < james_> sdfsd
07:49 -!- #ruby-lang Cannot send to channel

Attempting to sign in just does nothing at all. Literally nothing

/msg nickserv identify jimboF2 [email protected]

In IRC, (not sure what client you're using) you usually can change your nickname by using:

/nick NewName

And if you want to 'lock' that name for your own use (assuming no one else has registered that nickname, you do that command as what you have done:

/msg NickServ register password email

Which then NickServ will attempt to warn other people (when you're offline) if they are trying to use your name, saying that your name is registered, and they need to either:

1. Identify as you by doing /msg nickserv identify password (not sure if email is required, but it depends on the IRC server)
2. Get 'kicked' out by NickServ, or Forced-Name-Change by NickServ if you / the person using your nickname unable to identify themselves within certain period of time - again depends on the IRC server setting.

So looks like you have accidentally registered JimboF2. If you don't want it, ignore it, simply change your name to a name that you want to register, and try to register the name again.

Hope this helps.