Unfortunately no such exercise exists otherwise everyone would just do it. Results come from eating a balanced, healthy diet. You eat the right foods and quantities for your energy requirments and you will get results but nothing is fast. Unless you do some crazy crash diet which does more damage than good.
Fitness and health is a lifestyle not an infomercial you can just order when you want it. Exercise for life, not for the change of seasons. Life is all year!
Any exercise is good exercise but any full body workouts are good since...it's your whole body working. Burpees, skipping, rowing & squats I guess. But heck don't know what kind of results you're looking for
If you give more details what you're looking to achieve, weight loss, toning, bulking, etc. I'm sure someone will give way better advice. Good luck!