Complex sentence: Larsen's stepfather, a fan of country music, introduced him to the genre; by ten, Larsen had begun singing along to country karaoke tapes, and by age thirteen he learned to play guitar as well.
Split into simpler sentences: Larsen's stepfather, a fan of country music, introduced him to the genre. By ten, Larsen had begun singing along to country karaoke tapes, and by age thirteen he learned to play guitar as well.