This may be a stupid question....

There are three macronutrients (macros) - carbs, protein and fat. (Technically, alcohol is a fourth. But that's probably not worth worrying about right now.)

If you are counting macros (you don't have to. Calories are what you need for weight loss), how you calculate them is up to you. A basic macro split is 40% carbs, 30% protein, 30% fats. So if your calorie target is 1500 calories per day, that would be 600 calories of carbs (or 150 grams), 450 calories of protein (or 112.5 grams), and 450 calories of fats (or 50 grams).

One gram of carbohydrate = 4 calories.
One gram of protein = 4 calories.
One gram of fat = 9 calories.
One gram of alcohol = 7 calories.

If I were you, I'd just focus on logging all your food right now and hitting your calorie goal. After you get a bit better at that, you can then work on dialing in your macros a bit. MFP already has your macros split out in your food diary.