I know that "detoxing" is something that a lot of people talk about, but it's not a real thing. Your digestive system naturally detoxifies everything for you. And if your digestive system fails to do that, well, you've got a serious medical problem and you need to see a doctor.
You can take the idea of a "detox" and turn it into a week of clean eating. Eat only unprocessed foods, avoid caffeine and alcohol, and drink only water and caffeine-free tea. (Caffeine-free tea doesn't actually contain tea. Instead, it might contain rooibos aka "red tea," chamomile, mint, lavender buds, or rose petals.)
As for a one-week weight-loss diet, there's no such thing. From the photo you posted in Non-Hair, it looks like you're quite slim. So, you'd probably lose a pound of fat at best. Now, you could drop a lot of water weight by lowering your intake of salt and carbs, which could be useful if you have a special occasion at the end of the week. But once you eat normally again, you'll retain just as much water as before.