How can i improve cv/personal achievements for university application law courses

I'm in year ten and I want take law/history for degree. I want to get into Oxford or Cambridge, or perhaps study at an ivy league in America on an athletic scholarship. I row crew and am pretty good at it. I plan to maybe try and apply for a scholarship as lots of my older friends into sixth form have done so and are studying in America for so. It is early to say as I am young, if I continue my coaches are looking at GB trailing (UK rowing team). The problem is other than this I do not have lots of strong points that show ability. I am interested in debating and run a club for so, I partake in fundraising events and hope to be head girl one day. What can i do early on to prepare and make my personal statement/ achievements look better as all I do is rowing. I predicted 7s in most my subjects (which usually goes up by two grades within the year you have to prepare for your gcses). I want to perhaps do work experience, volunteering etc however I don't know how to do this for law, lost of courses require you to either be older or have to pay. Idk if this question makes sense but whatever lol ahhahah

For Oxbridge at least they won't care about all of the other stuff - they just want you to be good at your subject (a large part of which is doing well in the admissions test, but that's not something you should worry about until sixth form). Take debating club for example - they won't really care that you've taken a leading role in the club, but they might be interested in what you've gained from actually debating.

For UK unis the PS should be mostly academic, 75:25 academic : extracurricular ratio, or 80:20
For US unis if you run a club, head girl aand be descriptive (plus get good grades) then your extracurriculars aren't that bad for Ivy League (although you need to improve it).

You don't need to be exceptional at everything for Ivy League, many people get in with one extremely exceptional thing, and a lot of decent/alright things.

Thanks sso mucch for your response, I will keep this in mind. it it more difficult to get into ivy leagues as a international student from thee uk?