Your liver and kidneys already detoxify your body continuously. No tea improves on them.
What detox teas actually do: most contain senna or a similar laxative. The 1–2 kg you "lose" in a week is water and gut contents, and it returns within days. Prolonged use can cause electrolyte imbalance and dependency.
What actually works: a moderate calorie deficit, adequate protein, 25–30 g of fibre daily, sleep, and time. There is no shortcut, and anyone selling you one is selling you something.
If you enjoy green tea, drink it — it is a pleasant, near-zero-calorie beverage. Just do not expect it to do the work for you.