>>18446317
Eat food. Like alot of it. Calorie dense meals, high protein, high carb, low fat or high protein, high fat, low carb.
Experiment to see which makes you feel better and go from there. But you need to eat alot of food, force feed yourself for 2-3 days until your stomach expands then eat more for the next 3 days and etc. You will gain weight.

Most people with your problem are not consistent enough to gain or they think they're eating enough but they aren't.

Then with cutting, you just don't eat. Only protein and only enough to cover your needs.