Welcome to the intermediate program!
Assuming that you have established your stance and you know your jab hand, the next thing you wan to learn is a straight and hook. a straight and hook is with the hand that you don't use for the jab. you want to focus on pivoting during the swing. you plant your feet and your ankle, hip and shoulders moves with your arm, this make the punch much more powerful
Training routine:
20 sit-ups - 3 sets
12 push-ups - 3 sets
5km run - 2 sets
bag work/shadow boxing (practice what you have learned)