Yes, you can have lemon water with honey anytime in the morning -empty stomach , either before brushing & toilet or after it. here is no harm in both ways. Have little warm water and also for weight loss, try to reduce your carbohydrates and fat intake in your daily diet. Include protein rich foods in your diet like milk, yogurt, cheese, soybean, broccoli, sprouts and other dairy products (Vegetarian) and egg, chicken, fish (non-vegetarian). Increase the consumption of fruits, vegetables and salad in your diet as it contains fibres and vitamins.