There is no official curriculum for Mathematics Olympiad Competitions but the focus is on high-school level mathematics (so not calculus, linear algebra etc). Questions are divided into 4 categories: Algebra, Combinatorics, Geometry & Number Theory.

The following resources may be helpful for participants in preparing for PAMO 2023.

There are many past national olympiad questions available here including past PAMO questions (and some solutions) here.

If you are new to Olympiad problem solving, there is a lot of great content available provided by the Centre for Education in Mathematics & Computing at the University of Waterloo including a lot of past papers at different age groups.

The British Maths Olympiad also has a good selection of problems to work on.