Holbrook studied acting with the William Esper Studio's two-year Meisner Acting Program and with Shane Ann Younts' two-year voice and speech program, and he received an SCPS Certificate in 16mm film from New York University.
Holbrook belajar akting dengan Program Bertindak Meisner dua tahun William Esper Studio, dan dengan program pidato dan pidato dua tahun Shane Ann Younts, dan dia menerima Sertifikat SCPS dalam film 16mm dari New York University.