@randomelement Whether or not someone becomes skinny fat is down to their training, you can eat doughnuts and cupcakes and gain muscle too but the only way to gain is to eat more
But OP isn't asking about training, only about gaining weight
@theadmiral If you're already not getting optimal protein and only increase calories with donuts and cupcakes you will likely not gain additional muscle with those extra calories. But you will get fat.
@wannia Are you actively tracking your calorie intake? If not, then you should be. Use an app like Lifesum or myfitnesspal, so you can input what you're eating each day.
Also workout what your TDEE is (calculators are online) to work out roughly how much you're burning and how much you need to eat to gain weight.
@wannia Extra protein shakes. Use macrofactor or rp diet app. Drink like 4 protein shakes a day on top of what you’re eating. You should probably use a diet app to figure out what your maintenance calories are day to day and start eating 500-800 over that. Macrofactor will figure that all out for you over a period of few weeks and make adjustments.
@wannia Eat an entire pizza every single day. Get some hormel Chilli and some fritos and go to town, every single day. That's how I gained 40lbs over my tenth grade summer