i have been an ecto all my life. i weighed about 115-120 pounds in high school.. it sucked.. i started working out and eating better when i was 15 and made a lot of progress up until my senior year. enough where i was county champ in weightlifting and won a scholarship for football. you need to workout and put in the hours in the gym, i worked out 2 straight years from 16-18, even over the summer i would go in to my school gym.. there were about 20 of us commited .. it makes a huge difference, the more hours you put in while you are young the easier it will be to build muscle as you age
since then of course my diet has improved as i have aged and my metabolism has slowed. so be a lil patient and keep working at it and good things will come. your diet you listed is one of a typical teenager, its not gonna build you much of any muscle but it will keep your hunger down and get you through your day cheaply
in my signature below i have a bulking diet, it was designed exactly for skinny dudes like yourself.. its the same diet i used to bulk up myself and i did my best to keep it affordable cause i know young guys don't have much money to spend on food. you will look at it and be like shit none of those foods on there i ever even eat!! you aren't gonna build mass on peanut butter and jelly sandwiches or grilled cheese sandwiches.. or milk or protein shakes. none of those things are REAL FOOD. that what you need to learn, and thats the secret
PS: please don't have the attitude that just cause you are an ecto you can never build muscle.. thats bullshit and don't anyone ever tell you otherwise. its all gonna come down to diet and training. all things being equal i would rather be an ecto then be an endo. especially as you get older.