Complex sentence: When Idzikowski was sixteen, he moved to England, Anglicized his given name Stanisław to Stanislas, and began his performing career in London's West End, doing musical and ballet productions.
Split into simpler sentences: When Idzikowski was sixteen, he relocated to England, and Anglicized his given name Stanisław to Stanislas. His performing career began in London's West End, doing musical and ballet productions.