You can train at home aswell

Yes you can train at home.

You can :

Do press ups - this will help in smashing for badminton.

Do Sit-ups : This will help with your core strenght , and will help your overall game and help jumpsmashing.
And with your lady attrafcter - 6 pack.

Weights : Wrist curls will develop your game , they will strengthen your biceps - developing both your smashes and jumpsmashes.

Hope this helps!