As for the tea you mentioned, I can only say that it is a way to detoxify and relax the bowels, that is, to speed up metabolism and have certain effects. But it won't be very effective for you to lose weight. Losing weight is still a physical activity. You need to exercise more, control your diet and reduce your calorie intake, which will get twice the result with half the effort.
It is a three-point poison, which may be counterproductive, because the individual's physical condition is different.