Hi Lucy,
To loose weight you need to include both types of exercises like cardio and weight training exercises. Cardi oexercises helps to reduce your body fat percentage while weight training exercises would help to tone your body fat. Cardio exercises like running, jogging, skipping, swimming, etc. We need to do these exercises possibly every day or atleast 5/week for 45 min. And do weight training exercises like push ups, lunges, squats, etc for every alternate days for 20 min.