Hi, I'm sorry to ask but what would that be in lbs. ?
8 kg is 17.6 pounds and that's a pretty hefty amount to lose in only a month. You'd have to lose more than 4 pounds/week, which means cutting calories too low to keep it healthy.
Far better to implement a healthy eating and exercise plan that takes longer to lose, but will bring actual lifestyle changes, so you can keep the weight off, and won't have to worry next year.