Dear Paresh, there are many supplements available for health. Having said that, it is also important to know that there is no magical pill or tablet. Any safe supplement will only supplement your efforts and not be a magical solution.
Another aspect is the kind of weight loss you need. If you need 40kilos plus weight loss, the first thing is to supplement your diet with liver health supplements to ensure that your liver is efficient enough to digest your fat and remove it from the body when you begin your diet plan. If you have to lose 10-20 kilos then you only need some basic natural vitamins and a simple protein to ensure that you do not lose muscle weight while being on a diet.
Regarding exercises, please ensure there is enough cardio in your plan.