hellow everyone,

I am in desperate need of some help from you guys.. Any doctors or nutrition experts help me out plz...here is the problem...I am a male 22 years old weighing only 120 lbs. I am 5'9" and i know for that height I am skinny..I did some research on the internet and came up to the fact that I need to eat 2500-3000 calories but, the problem is EAT WHAT??? I have a real busy schedule and as of rite now I eat once or twice a day(like fast food and stuff)..and sometimes more than that...anyone that can help me with this plz do...I feel I am weak and feel like passing out every once in a while...my ears keep ringing donno why..I get paranoid thinking that I will die coz I dont eat enough..but I dont like eating everything..(kinda picky) plz help..