What do I need to do to have a chance of being accepted into Oxford or Cambridge?

I am a 17-year-old from Perú. I've completed secondary school and am currently enrolled in a pre-university academy aimed at preparing students for the Universidad Nacional de Ingeniería, which hosts one the toughest entrance exam in South America. Here, I'm studying a broad range of subjects including algebra, geometry, arithmetic, trigonometry, physics, chemistry, philosophy/logic, mathematical reasoning, history, verbal reasoning, economics, geography, and language.
Next year, I'll be relocating to Luxembourg to pursue AS-Levels in Chemistry and Computer Science, and A-Levels in Physics, Mathematics, and Further Mathematics in September 2025. Additionally, I aspire to participate in the Physics Olympiad and attend summer camps focusing on science or programming. I’ll also have a C1 proficiency certificates in French and English by the end of 2025. And I am also learning C++ through an Udemy course.
Given my ambitions, what are the likelihoods of being admitted to Oxford or Cambridge (Physics or Physics and Philosophy)? What additional steps should I take to enhance my prospects?

I am a 17-year-old from Perú. I've completed secondary school and am currently enrolled in a pre-university academy aimed at preparing students for the Universidad Nacional de Ingeniería, which hosts one the toughest entrance exam in South America. Here, I'm studying a broad range of subjects including algebra, geometry, arithmetic, trigonometry, physics, chemistry, philosophy/logic, mathematical reasoning, history, verbal reasoning, economics, geography, and language.
Next year, I'll be relocating to Luxembourg to pursue AS-Levels in Chemistry and Computer Science, and A-Levels in Physics, Mathematics, and Further Mathematics in September 2025. Additionally, I aspire to participate in the Physics Olympiad and attend summer camps focusing on science or programming. I’ll also have a C1 proficiency certificates in French and English by the end of 2025. And I am also learning C++ through an Udemy course.
Given my ambitions, what are the likelihoods of being admitted to Oxford or Cambridge (Physics or Physics and Philosophy)? What additional steps should I take to enhance my prospects?

you should definitely include some super-curriculars ! read physics books, listen to podcasts, sign up for MOOCs, volunteer at a lab if possible, all good things oxbrige LOVE on applications. it shows them how passionate and promising you are in your chosen subject, which is exactly what they look for

Here is a useful site for practicing Physics questions.
https://isaacphysics.org/alevel?stage=all
Read about courses on different University websites to confirm which course you are most interested in. You may find you prefer a course at a completely different university. (There are many excellent universities.)
The Cambridge course is Natural Sciences (Physical) so it may be more useful to do A level Chemistry instead of AS if you want to apply to Cambridge.
Pay close attention to the University website for guidance on the application process.
To help build confidence for the interview practice answering maths and physics questions out loud to someone else. If you are unsure how to proceed with a question ask for clarification.
The application process is competitive. Many highly intelligent people will not get an offer as places are limited in number. Therefore, also apply to other universities that you would be happy to attend. Good luck and enjoy the challenge!