Complex sentence: He auditioned at Woollim Entertainment to pursue a career as a solo singer, and was accepted into Woollim along with 2 other agencies, one of which being YG Entertainment.
Split into simpler sentences: He auditioned at Woollim Entertainment to pursue a career in music as a solo singer. At that point, he was accepted into Woollim along with 2 other agencies, one of which being YG Entertainment.