I hate exercising - how to lose post partum the belly fat?

If you are breastfeeding, it will help with losing weight. Especially with you keep to a healthy and well-balanced diet (don't need to go on a diet as you will need the nutrients and energy for breastfeeding). Just ensuring that you are eating well and taking in adequate amount of fluid will help. Even if you are not breastfeeding, you can achieve your weight lost goals by keeping to a clean, healthy diet. The results will be better if you could keep an active lifestyle. If you are not inclined to exercise, just walking more, taking the stairs (instead of lifts and elevators), having an evening walk with your partner and baby after dinner will be good too. Very importantly, don't go on a crash diet as the results will not be sustainable. Eating well is key though it may take longer for you to see the results. Take care!