try to find the network icon in the Linux panel, left click it, then left click something that looks like "auto eth0". see if that works.
if it does you can set it to connect to the internet automaticly by:
1. left click the icon
2. click "edit connections"
3. under "wired" click the name of your connection (the same as in the list i.e. 'auto eth0;)
4. click 'edit'
5. put your password in for the admin prompt if necessary
6. click the checkbox 'connect automaticly' under 'wired'
7. click 'save' do the prompt if necessary
8. click 'close'
now you will connect automaticly each time you boot. to disconnect left click the icon and click 'disconnect'