Complex sentence: Convinced that the Bnei Menashe were descendants of Israelites, he worked to convert them to normative Orthodox Judaism and facilitate their "aliya" with funds provided by benefactors such as the International Fellowship of Christians and Jews.
Split into simpler sentences: Convinced that the Bnei Menashe were descendants of Israelites, he worked to convert them to normative Orthodox Judaism. He also worked to facilitate their "aliya" with funds provided by benefactors such as the International Fellowship of Christians and Jews.