Complex sentence: American industrialist John D. Rockefeller reportedly made his first large donation for public welfare and later became a notable philanthropist after a netting with Vivekananda in which Vivekananda made Rockfeller understand that, his money was only a channel to help the poor and distressed people.
Split into simpler sentences: American industrialist John D. Rockefeller reportedly made his first large donation for public welfare and later became a notable philanthropist after a meeting with Vivekananda. Vivekananda succinctly explained to Rockfeller that his philanthropy would only be a channel to help the poor and distressed people.