Every day you burn a different number of calories for various reasons; the thermic effect of food (the energy your body uses to digest, and process food), the thermic effect of exercise which is the energy your body uses to complete any task beyond it’s normal daily functioning such as breathing, pumping blood through your heart, etc.

The number 2,655 is a ballpark number; it should be pretty close to your maintenance. In theory, you would stay at the same weight by eating 2,655 calories each day.

Here’s some basic trainer math. 1 lb of body fat = about 3,500 calories worth of stored energy. If you were at a 500 calorie deficit each day for a week, theoretically you would lose 1 lb of body fat every week.

Reaching a 500 calorie deficit should come from a combination of diet & exercise.

Conversely, you would gain about a pound a week if you ate 500 calories more than your maintenance level each day. Even if you exercise away 300 calories every day, you still have a surplus of 200 calories. Our body stores that extra energy as body fat.

I hope this helps.