I don't know what I'm doing it looks like when I connect I'm on but theres no chat screen that comes on and then sometimes it saids must register nick already did that (maybe I'm not connecting the right way?) please help

You need to join a channel after you connect.

Try this to see...

Type:
/server irc.undernet.org

After connected:
/join #help

If it says you need to be registered, then you have to register your nick on the network to use the channel. Networks don't all do this the same way, so you should go to the #help channel on whatever network you're on and ask how. Sometimes those instructions are in the #help channel's topic. Just as a note, most servers that ask for you to be registered probably use Nickserv. If that's the case, typing /nickserv help will give you the list of commands (including the REGISTER and IDENTIFY commands). Once registered, you have to activate the account (check your e-mail for how). Then, everytime you connect, you need to identify (i.e. log in) to your registered account.

I put in / server irc.undernet.org this is what came up Memo is on IRC what is that where is that?

Is your nick "memo"? You should be able to just type those 2 commands that I mentioned and it should work fine.

I'm not getting no reply.