Hi
Let's guess what you need to do. I'm gonna try some possibilities. If it works, ok. If not, post again with more information about your system.
First, you should try to run netconfig. It's a cool tool.
For a simple configuration it should work (supposing that you have direct connection e. g. a fixed IP; or only dhcp with direct connection and a dedicated router managing the harsh aspects of your connection). Remember that you have to have the modules already configured for your ethernet card (usually netconfig also does that).
In doubt? Type ifconfig whitout parameters. It should show you your net interfaces (in your case, maybe eth0 and lo). If dhcp is running, you should see the IP. Now try to ping a machine you know it's outside your local loop (e. g.
www.linuxquestions.org). If it gives you a response, that means you have internet connection. In that case, congratulations!.
If not,
-maybe you have a working connection but also a dns resolution problem. (e.g. you can ping 64.179.4.149 but not
www.linuxquestions.org).
or
-maybe you have to connect through a vpn. (in case that even when you have dhcp resolution and an IP, you are still not able to connect to internet).
My advice: try netconfig first. If it doesn't work, post again.
Good luck.