1st and 2nd must be in userlist one Admin:NICK and then with the command !add you can add more Admin: and OP:
The OP Can be !op and !deop like Admin
The Admin Can be !op and !deop and !add admin/op.
3rd
The nick with the level 3:Nick can add new admin (!add) can (!op and !deop)
The 2:Nick can be only !op and !deop