Each network has their own policies, not all have channel registration and services. As Merlin said, read the MOTD when you join, go look at the networks website (www.google.com
should find it for you easily) or see if the network has a #mIRC that could lead you in the right direction.
In general, if you want to be an op in someone else's channel, its up to them if they want to add you, each has their personal rules. Usually you can start your own channel by just typing /join #somecutelilchannelnamehere. Whether you will have channel services to register it and op you when you join or need a bot to hold it for you, is up to the network.