Whether you eat 3 times a day or 10 times a day doesn't matter...
Actually it does, in regards to keeping your metabolism reved up, and nutrient partitioning.
As far as calories you need to figure your BMR/RMR: Here is a link to a BMR calculator:
BMR Calculator
But here is the formula if you are into this geeky stuff like me
For Men
BMR = 66 + (13.7 x weight in kg) + (5 x height in cm) - (6.8 x age)
For Women
BMR = 655 + (9.6 x weight in kg) + (1.7 x height in cm) - (4.7 x age)
Your BMR aka RMR is the rate your body will burn calories if you did absolutely nothing.
Then you need to factor in your caloric expenditure and times your activity level factor*BMR will equal your Daily Energy Expenditure
Activity level factor/Activity level
1.0 - Sedentary (doing nothing all day (sleeping and watching TV)
1.2 - Very light activity (Working a desk job or on a computer and not performing any type of physical activity during your day)
1.4 - Light activity (having a non-physical job (desk, computer, etc.) but performing some sort of physical activity during the day (e.g. above average walking) but no hard training.)
1.6 - Moderate activity (non-physical job, performing some sort of physical activity during the day, and including a daily workout session in your routine)
1.8 - High activity (training plus a physical job or non-physical job and twice-a-day training sessions)
2.0 - Extreme activity (very physical job and daily hard training)
So, your DEE = activity level factor*BMR. This is maintenance
Bulking you want to start at about 120% of your DEE and adjust accordingly
Cutting start at 80%*DEE and adjust accordingly
Types of food as OCCFan023 suggested, except don't forget a 1-2 serving of veggies each meal and mix in some fruit and fish oils.
When I cut, I will not eat any starchy carbs unless I just exercised, otherwise my carb sources are veggies.
And try mixing in some HIIT sessions which is more intense and will burn more calories than regular cardio.