Complex sentence: Many of the dispossed Jews found refuge in Alexandria, Egypt, where Naeh opened a "yeshiva" called "Yeshivat Eretz Yisrael" which consisted of 200 students who had been exiled from Jerusalem.
Split into simpler sentences: Many of the dispossed Jews found refuge in Alexandria, Egypt, where Naeh opened a yeshiva called "Yeshivat Eretz Yisrael". His yeshivah had 200 students who had been exiled from Jerusalem.