I wouldn't suggest a detox. Most of the experts say a detox isn't necessary because the body does a good job at it naturally, and most detox diets or products can be dangerous. If you eat healthy foods for a few days, drink plenty of water, then your body will naturally detox itself.
Are you going to the meetings or doing WW online? You can get sample menus to follow and as long as you stick to them, you'll be guaranteed a good start