Complex sentence: After he graduated from Georgetown Prep school, he moved to the UK and studied at Oxford University, majoring in PPE (Politics Philosophy and Economics) and received B.A. and M.A. degrees.
Split into simpler sentences: After he graduated from Georgetown Prep school, he moved to the UK and studied at Oxford University. As an undergraduate, he majored in PPE (Politics, Philosophy and Economics) receiving B.A. and M.A. degrees.