IRC help

[Cosmology27]

So I'm going through to get permissions, and the Big Reactors creator has nothing except an IRC.
IRC
Network: SynIRC
Channel: #bigreactors

I've never used this before, and the site doesn't really make sense to me. I'm sure this is a super easy thing to do, so I thought I'd just ask. How do I contact this person using https://www.synirc.net/

Thanks for the help!

 

[Padfoote]

Under "Main", click "Webchat". Enter a username and that channel name, hit join.