Complex sentence: He found work as an office secretary at Universal Pictures'New York office, and eventually worked his way up to be personal secretary to the studio's founder and president, Carl Laemmle, where he was paid $25 per week.
Split into simpler sentences: He found work as an office secretary at Universal Pictures'New York office. Relatively quickly, he worked his way up to the position of personal secretary to the studio's founder and president, Carl Laemmle, under whom he was paid $25 per week.