How many calories should I consume a day to lose 2 Kg per week?
About 15,000 / 7 days, so a little over 2,000 per day need to be lost.
It's very hard to calculate how many calories to consume. First, you need to know your BMR- basal metabolic rate. That's the number of calories you burn just by existing (heart pumping, digesting food, brain using oxygen, and so on), and it is calculated by age, sex and weight.
Then you need to figure out how many calories you burn each day- type of work, exercise done, etc., and so on.
IF you are not gaining or losing weight right now, then it's a little simpler. Just do whatever you're already doing, but adjust for a 2000 calories deficit. I recommend cutting your diet by about 500 calories, and finding the time to do about 1500 calories worth of exercise each day.
Not easy, but doable.