If you've got a knack for maths olympiads like the IMO, and you know some probability: you're quite well set for an internship at a high-paying company in finance. More often than not, they really value maths olympiad folks... The creator of the content below, also an IMO-person, confirms this :)
Moreover, it is not only useful for university and graduate life (unlikely, sadly, Euclidean Geometry), but is also not that far in style from what you have been doing! In particular there are "tricky" problems, unexpected applications and cute problems, that people liking maths for its beauty will certainly appreciate.
The journey below is for people who have around 1-2 years of high school left. In particular those aiming to take part in a national olympiad or, even, IMO should find this interesting & challenging enough.
Key words: lots of problems, basics of discrete probability, expected value, some olympiad stuff.
Key words: Theoretical dive into probability theory, continuous & discrete worlds, two modes: high school / uni.
If you have at least 3 years of middle/high school left before the university, you can still be doing some probability! Why not, the content of the initial courses is not theoretically heavy at all...
But we would suggest going through the Casual Learning plan first though, just to get a taste of "why probability" and "where probability". If you are determined enough, you can open the "Probability From School" plan right away (it is the next step after "Casual Learning").
Next Steps
Once you are familiar with the content from above, and if you are in the first/second year of university, you can start the "Getting into Finance" plan. There are other great options you can explore, like "research", it is just trading ones pay crazy well and they require simpler theoretical background.
However, you may struggle getting an offer since "you are too young" :) Therefore, it would not hurt to continue studying probability & statistics, in particular get to Linear Regression (course PA-9). From there, even more doors are open.