Besides kilocalories, your nutrition screen also shows your macros. Here’s briefly what they are and why they’re counted separately.
Kilocalories are the energy in your food. They aren’t a separate nutrient but the result of the other three: protein and carbohydrates provide about four kilocalories per gram, fats nine. So two days with the same calorie goal can be made up very differently.
Protein is the building block for muscle tissue and recovery. With strength training and when losing weight, this is the macro most coaches steer on: enough protein is what decides whether you keep or lose muscle in a deficit. That’s why this app treats it as a minimum and not as a target.
Carbohydrates are your fastest fuel and the main source for hard workouts. They aren’t ‘bad’; how much you need depends on how hard and how often you train.
Fats are needed for your hormone balance and for absorbing certain vitamins. Going too low backfires.
Sugars are part of your carbohydrates, not a separate category alongside them. They’re counted separately because some coaches set a ceiling on them.
Where your goals come from. If you have a coach, they set them. Without a coach you fill them in yourself, and the ring on your nutrition screen starts filling as soon as you have.