Is it necessary to have breakfast everyday. I live in the hostel so since I wake up hostel, I often miss breakfast. Is that cool?

Most impt meal of da. Just like your grandma told you. Jump starts your metabolism, provides calories, protein for your brain to use (maybe with less caffeine); prevents overeating later in the day. Studies confirm better test scores and work output in people who eat breakfast. Also better success with weight loss and weight maintenance.
It's not cool. Missing breakfast is a sure way to develop weight gain problems. Break the fast!