In the end, it is though. Over time, If you create a calorie deficit, you lose weight and if you create a surplus, you gain weight.

However, how much you lose or gain depends on a lot of factors. And most importantly, when we lose weight, we are fighting millions of years of evolution to not eat. So the diet fatigue is real.

But if you take your current weight, measure your daily calorie intake for a week or two and then slightly reduce your daily calories below that intake, you will lose weight.