First of all, if u want to loose ur weight, u have to put in order ur nutrition. Simply, u have to spend more calories than u eat. Actually, u can also eat hamburgers, chips and sweets and u will lose ur weight, but u have to eat that things in very small quantity. If u ask me, that's stupid, but it works if u eat less calories than u spend. So, my advice is, to change ur eating habits. Of course, it would be great if u also start to exercising. So, u have to have at least 5 meals per day. I am not talking about big meals, but small, that make you feel fed for approximately 3 hours. Eat enough of proteins, complex carbo hydrates and healthy fats. Don't forget to dring enough of water. So, green tea, pu erh and other fat-burning teas are just kind of a supplement that can help u, but the most important thing is ur nutrition. It is good to drink tea before exercising, cuz caffeine is a stimulant. So, if u have any other question about nutrition (or anything else), just ask and I (or somebody else) will try to answer

Wish u all the best!