For weight loss, dieting is more effective than exercise.
Supper needs to be abolished as supper calories are even more fattening than dinner calories as you don't burn them up with most of the day behind you. Breakfast calories are the least fattening followed by lunch calories as you burn them up with most of the day ahead of you.
Reducing your intake of junk sugar will help. Foods or drinks such as coke and other soft drinks, desserts, sweets, cakes, cookies or biscuits must be eliminated or substantially reduced. Cereals must be restricted to those that contain less than 15% total sugars and junk sugar loaded foods such as pizzas must be avoided. Junk sugar bowls must be abolished. Oatmeal, oat bran, wheat bran and wheat germ are good cereals that can help for weight loss.
Junk sugar health hazards are discussed in a web search for "sugar health hazards".
The natural sugars in fruit and vegetables are OK as they metabolise to glucose slowly due to their high fiber content so they have a low to medium GI value. Fruit and vegetables are low in calories and are not fattening. Most fruit and vegetables are metabolism boosting foods and that helps for weight loss. Potatoes and sweet potatoes are exceptions and can be fattening.
Fattening combinations that you need to avoid include combinations of protein foods (such as eggs, meat, poultry, sea food, cheese and nuts) with starchy carbohydrates (such as bread, cereals, pasta, rice, potatoes, sweet potatoes and corn).
Apparently the Lemon Detox Diet is the worst diet there is as in a web search for "lemon detox diet" + voted + worst.