It's definitely possible! Just start raising money now so when u get out of highschool/college you can purchase your own horse!
Yeh for sure as long as you are committed and train often
Of course it's possible! I don't have my own horse either. I started riding at 12 (now 17). It depends on how many hours you spent riding and it depends on you. If you want it, you can do it, no matter how hard it is.
Yes of course one of the olympic riders at rio didn't start riding til he was 14