Westminster Sixth Form 2023 Entry

Hello everyone! I am an international student from China, and I am seeking to move to Westminster School in 2023 at 16 . I am going to study Math, Physics, Biology and Chemistry in Sixth Form. I learnt GCSE(only these four subjects)and received several suggestions from students who studied in Westminster. However, I am still not sure about the details of entrance exams and how can I prepare for it. Could anyone give me some advice on the entrance exams in November please?1.Should I do a lot of CIE past papers?2.Will studying A-level content help?Thank you!!!