Yes, TDEE is an important number that helps you manage your weight. To calculate it, you need to enter your data: gender, age, weight, height, and physical activity level. I use
tdee calculator. This calculator is quite easy to use. First, it calculates your BMR (basal metabolic rate), and then multiplies it by your activity factor. This will give you your TDEE. If you want to lose weight, you should consume fewer calories than your TDEE. And if you want to gain weight, you should consume more. I hope this helps you in your training and nutrition!