Complex sentence: He attended his high-school years in Sergio Osmeña Sr. High School and he took up B.S. in Physical Education at the University of Santo Tomas being a student and an athlete at the same time.
Split into simpler sentences: He attended his high-school years in Sergio Osmeña Sr. High School. He took up B.S. in Physical Education at the University of Santo Tomas, being a student and an athlete at the same time.