My first time riding Moah! He pulls alot thou and likes to rush forward if he sees a horse in front. Had to make sure i kept him within a reasonable distance from the others. First time also cantering in a group. Challenging but fun! 
NOTE: No criticisms please as I’m still learning as a junior rider and considering some of the horses here aren’t the best behaved/easy to ride ones.
In the posting trot your over posting, try staying a little bit closer to the saddle, and your hands should be staying down not bouncing with your body, and try to lean back . In the canter push down in your heels and minimize tge movement in your waist, lean back more and keep your upper body still. Also your reigns should be shorter and your hands should push forward and come back with the horses movement. I can tell your a begginner though and for your level it was good.
Cool !!! Nice trotting n cantering!!!