I would give you two alternatives of training. Note that in either of the two options you can practice different types of aerobic exercise preferably running, riding a bike or elliptical machine.
The first is recommended for beginners and consists of a session of 5 intervals of 4 minutes each row to complete all 20 minutes of exercise. Each range will consist of three minutes of low to medium intensity followed by a minute of high intensity. These intensity changes elevate your oxygen consumption post-exercise which results in burning more calories at rest after exercising.
The second alternative training is exercising 10 to 15 minutes at high intensity followed by 20-30 minutes on low or medium intensity. This will cause most of the calories you consume during exercise come from fatty acids accumulated in your body without completely sacrifice your glycogen stores which will be necessary in such case you want to supplement your exercise routine with weights.
The VO2 max is the maximum amount of oxygen that the body can absorb, transport and consumption per unit of time, the maximum volume of oxygen in the blood that the body can transport and metabolize.
Studies show that there is a correlation between heart rate reserve and VO2max. The HRR is calculated by subtracting your maximum heart rate from your resting heart rate. A very useful Argonne formula is that it is 220 minus your age. Suppose you have 20 years with a resting heart rate of 60 beats per minute, the maximum heart rate for your age group should be 200 and your HRR would be 140. Suppose you want to train 60% of your VO2 max should simply multiply your HRR by 60 which would be 84 beats per minute. To translate this into a normal heart rate, simply add the resting heart rate to 84. This would give 144 beats per minute, or 72% of your maximum heart rate.
Is it still too complicated? In my book 7 kilos, seven weeks included a calculator to VO2 max.Ideally you make either routine 5 days a week then remember that is an intensive plan.
With this plan you could stand to lose between 4-8 kilos in two weeks depending on your weight, body type and current metabolism. It is important not to change your food consumption in other periods of food because if you increase your carbohydrate servings at breakfast and / or lunch the plan would not work. Do not forget to drink plenty of water.