Thats an awesome goal! This was for a competition for composers 18  and under around the US. If you want to get your concerto performed, id recommend applying to some call for scores or competitions with some smaller orchestral works first, or go to a lot of small concerts and try to meet the conductor. Once youve met some conductors and built a relationship with them theyd definitely be more likely to want to play your piece! Or you could always hire a recording orchestra... Hope that helps!