Sedentary adults typically need 1,600-2,200 calories per day depending on size and age. The sedentary activity multiplier (1.2) accounts for basic daily movement like walking around the house and office. Any intentional exercise would move you to a higher activity level.

Yes, because your total calorie burn is lower, leaving less room for a calorie deficit while still eating enough to feel satisfied. Adding even moderate exercise (a daily 30-minute walk) can increase TDEE by 200-300 calories, making weight management significantly easier.

You can, but keeping calories consistent is simpler and often more sustainable. If you prefer to vary calories, reduce by 100-200 on rest days and add them on active days. The weekly calorie total matters more than daily variations.