Complex sentence: Later he moved to Milan, where he frescoed a hall in the Castello Sforzesco; he subsequently realized works in Novara, at the Abbey of Chiaravalle and other ares of Lombardy.
Split into simpler sentences: Later he moved to Milan, where he frescoed a hall in the Castello Sforzesco. He subsequently created works in Novara, at the Abbey of Chiaravalle and other ares of Lombardy.