U need 50 kgs weight loss.don't run behind fast weight loss. Try to achieve permanent weight loss. Through good lifestyle you can achieve it. And once weight loss should not bounce back. No fat burners as they have side effects. Once u stop weight  will bounce back

Fast weight loss meaning fast weight gain too. So think practically you need to put in dedicated efforts in physics activites likes out door sports and games given u r age of 23 u must do at least 2 hours of sports, cardio and running all 3together. Secondly a well balanced nourishment plan so that u dont get exhausted and loose weight same time.

You have gained a lot. It's necessary to shed 30 to 35 kgs need regular and consistent focus on  diet,physical activity and your daily routine. You can reduce 3.5 kg by reducing 500 Calories from your daily caloric requirements for a month, so yo need to work hard for 1 year continously under the guidance of a good dietitian for continuous help and support. Patience, faith in your dietitian and regular disciplined caloric intake and output management is required to achieve the goal. If there is need then only any supplementation is required.

I agree 105 kg weight is too much but you should with diet & exercise. If not you have options like green tea & obicure supplements which help in weight loss. You can talk to your doctor & opt for some weight loss surgery. Ideally fat burners are not safe they might have some effects, majorly nutrient loss. Yes definitely they help weight loss but it should not be at the cost of your health. As u said u can join gym & do cardio, weight training & Abs to help loose weight