Complex sentence: By the time he reached his teens, he was paying for his own education by accompanying and performing; he continued to do so throughout high school, adding church organist, orchestral player and radio staff pianist to his experience.
Split into simpler sentences: By the time he reached his teens, he was paying for his own education by accompanying and performing. He continued to do so throughout high school, adding church organist, orchestral player and radio staff pianist to his experience.