If i burn at least 2100 calories a day what do need to maintain my weight now.

Same amount: It's basic physics, really; if you burn 2100 calories a day, you will need that same amount to stay at your current weight.

Create Balance of En: To maintain healthy weight, you need to create energy balance between your caloric expenditure and intake. All foods have a food value(number of calories)...So you need to consume foods that add up to about 2000 calories/day. By the way it is quite hard to burn 2100 caloris per day. I hope you ar including the basic caloric needs for the body to run the basic metabolic rate plus what you burn.