Help? i really need to gain weight!?

do you want to gain weight or gain size? because if you want to gain weight, i would say eat a lot more and exercise a lot more too. muscle weighs more than fat does. i also have a high metabolism, and i've also had problems with my mom thinking i dont eat. in a box of my favorite mac and cheese, there are 2.5 servings and i can eat all of it except about 1/4 of a serving. and it does nothing to me lol. maybe try researching foods that have a lot of carbs? maybe start eating a lot of bread products? im not really sure. if you actually want to get bigger in size, maybe try skipping breakfast. i know its not healthy or anything, but if you do that your body keeps more nutrients or something and uses them slower i think. thats why they tell people that want to lose weight not to skip meals. so maybe try skipping breakfast and eating a big lunch and dinner? i hope this helps a little :)