Add user with password: net user /add *username password
Ex: net user /add Madison password

Set user as local administrator: net localgroup administrators username /add
Ex: net localgroup administrators Madison /add

Delete user: net user user name /delete
Ex: net user Madison /delete

Set password never to expire:
wmic UserAccount where Name="username" set PasswordExpires=False
EX: wmic UserAccount where Name="Madison" set PasswordExpires=False