Hello Nikola,
To be op on a registered channel as #skopje is (to check if a channel is registered or not u can use /msg x isreg #channel-name) or to op yourself on such a channel, you have to register an username first. For that you have to go to
http://cservice.undernet.org/live click on Register new, a mail is needed to register, most of the free emails are blocked due to abuse (is allowed one username per person only) - that's why we recommend to use a mail from your internet provider - the company you pay internet bills. If you don't have home internet connection you will have to find a valid email. So fill the form on that page, after that confirm registration - an url is sent in email you provided.
After that to login to X use /msg
x@channels.undernet.org login your_username your_password, keep the password for you only, is not allowed to share it, also DO NOT give if someone says that is (from) cservice or that channel service has problems - thats a fake.
After loging to X you will be able to use X - this is the undernet official bot of channel service. To use it on a channel you need to have access on the channel. Access means levels from 1 to 500 (500 being the channel manager). According to your level on X you can use different cmds. To see what cmds you may use just type /msg X showcommands #channel-name.
For example to op yourself on a channel you need at least level 100. Only 400 or higher level access may add new users to access list. You will have to talk with them, this doesnt mean you will get access there as most of the channels have rules for this and for being promoted to op.
Finally, to see a list of all X cmds by levels please visit
http://cservice.undernet.org/docs scroll down there to X command list in different languages and file formats (txt, chm, ...)
If something is not clear about X commands or registered channels please type /join #cservice on irc.
If you need help related with your username /join #Usernames.
Welcome here and wish u a great time here !!!