My very amateur understanding (as a new Grokker member) is that calorie needs vary from person to person according to gender, age, height, current weight and metabolism in addition to quantity of weekly physical exercise. I have read that many women require about 1800 calories per day, but that figure is a generalization. Dr. Chris Mohr offers three "Nutrition 101" video programs that might help reframe our thinking to encourage us to build nutritious meals rather than count calories:
https://grokker.com/cooking/program/fuel-your-workweek/5e28c8354b5ba63fda11aa5d
https://grokker.com/cooking/nutrition-101/program/21-day-nutrition-reboot/5a1c8d5075c30566d6921591