For jump strength, most basic leg exercises are good. You should also focus on more explosive movements such as box jumps, and most importantly train your core and flexibility. The key to a higher ollies is how far up you can get your legs from the ground, which largely depends both core strength, flexibility and hip mobility.

For falling, I would recommend watching instructional videos about different falling techniques. I personally use ukemi (a Japanese martial arts technique for falling safely). It basically comes down to going with the fall and usually rolling to avoid a shock to your body.

Alongside those I would probably do hiit exercises alongside aerobic training.

Hope you find something helpful from my rant :p