just go into your pc networking config and enable sharing via the lan port
Now your lan port with be used to connect to the internet
only problem you may have if your service provider does not allow Dynamic DNS Service
many dont allow like cat telkom - But then you just change your DM config and put a real ip to the connecting server .
Only problem with this setup your PC will need to be ON all the time
Once you turn off PC the connection to lan host will discconect service