...
If “Send a password reset link“ is disabled, then a password for the new user must be entered by the administrator. The password must meet all the complexity requirements, see Settings - Configuration - Security - Password rules.
First name and Last name
...
It is used only for information purposes and easier orientation of the administrators. It is not used anywhere by the application.
IP ranges
Individual IP ranges from which the user accesses the application. For details see Settings - Configuration - Users - User restrictions by IP ranges.
Preferred language
The language in which all e-mail to this user will be sent can be set here. This setting has a higher priority than the global e-mail language set in Settings - Configuration - E-mail. The user can modify this setting on his own in his profile after login.
...