eat in a deficit! lol jk... calories in/out matter, but not as much as people think. i mean obviously if you eat 10000 calories a day you aren't gonna lose weight. but the key to fat loss is hormones #1 more than worrying about how much calories you eat
one of the best ways to fix a diet so that you fix your hormones is eating a natural whole food diet in a time restricted window of 2-6 hours. the benefits aren't just fat loss, but they are immune boost, autophagy, gut health, organ health etc etc.
this type of eating style is referred as intermittent fasting, but i hate that term. i call it time restricted eating. you can eat the SAME exact calories spread out or in a window and have 2 completely different end results