Buy a ticket and join the crowds at a game at Taitung Stadium. If there's nothing scheduled while you're there, you might like to check if they give a guided tour of the grounds.
This sporting facility in Taitung City Centre is well-liked by fellow travelers, so make sure it features on your travel plans. However, don't end your sightseeing there. There are plenty more places waiting for you to enjoy after Taitung Stadium. Fugang Fishery Harbor, Taitung Railway Art Village, and National Taitung University are not far away.