I spend quite a lot of my time on Freenode as it has so many useful channels and people that can help you.
Here are the IRC channels I often frequent:
Textual keeps a command reference here.
/list - Open channel list.
/msg *nickserv set <yourNSpassword> - Lets Nickserv autologin you. Can then run
/nick <your-nick> to login.
If I ever get issues with logging in and me being Guest. I can:
/msg NickServ RELEASE <nickname> <password>
/nick nikivi my nick
IRC Gitter - Connect to Gitter with Textual.
BotBot - IRC logs.
picobounce - IRC bouncer that does just what I want and no more.
Irssi - Modular chat client that is most commonly known for its text mode user interface, but 80% of the code isn't text mode specific.
RobustIRC - IRC without netsplits.