To start your fitness journey you need to know a few details.
BMR is your Basal metabolic rate i.e. if you did absolutely nothing all day, it is the number of calories your body uses to sustain life.
TDEE is your total daily energy expenditure. It is BMR plus the number of calories burnt through activity.
Macro or macronutrients are nutrients that your body requires in large quantities such as Fat, Protein, Carbs, Water, and Fiber. A good balance of these macronutrients is essential to your fitness goals.
Your body fat% is a key indicator of your good health. A high body fat% is not only undesirable, but it also puts you at a higher risk of lifestyle diseases. A body fat% of 15 or less is recommended for males while a body fat % of less than 25 is recommended for females.