Not familiar with the Pantech -- but let's assume that it's a simple ADSL or Cable modem which attaches to computer by USB.
1) You could link the second computer to the first by Windows Internet Connection Sharing and a crossover ethernet cable. It's not an option I would choose because both computer have to be running and ICS seems a little flaky.
2) Replace the Pantech with a modem/router* appropriate to your connection (ADSL or Cable) so ask your Internet Provider before buying -- they may have a recommendation and can guide you on setting up the new device to match the ISP's required settings.
*Confusingly modem/routers are simply called routers and most now come with wireless at very little extra cost -- which adds flexibility.
Can't find your answer ? Ask !
Read discussions in other Wireless Networking categories