it depends on what your daily caloric intake goal is. Lets say its 2000 calories a day-divide that into 4ths. 1/4 breaksfast , lnch, dinner, the remaining 1/4 is divided up for snacks throughout the day.
breakfast relly is important tho because it sets your metabolism for the day. If you skip it or eat too little, your body goes into starvation mode.