1.) Don't confuse your goals
Your goal is NOT to lose as much weight as possible, as quickly as possible. The goal is to master your diet and learn the process by which you learn this vital new life skill. That means, ultimately, mastering yourself. Learning your triggers, training new habits, investing your time and deep focus on taking back control and healing your relationship with food. You will lose weight as a result of your committing to the process. After you master your diet, you will be in an informed and empowered place to strategically add more physical exertion to your load - if it's even necessary at all.
2.) 80% of your body composition will be determined by your diet
Source : http://uk.businessinsider.com/how-to-lose-weight-without-exercising-2017-4