Complex sentence: She is then called to the Fortress of Solitude, where she is told by the A.I. of Jor-El that her job on Earth is done, and then using a Legion of Super-Heroes Ring, travels to the future to seek her own destiny.
Split into simpler sentences: She is then called to the Fortress of Solitude, where she learns from Jor-El that her job on Earth is done. Using a Legion of Super-Heroes flight ring, she travels to the future to seek her own destiny.