Typically a diet is a temporary and often extreme change in the way you eat, in an attempt to reach a specific goal or weight. However, when choosing a new eating lifestyle you are committing to a long term mindset shift surrounding the food you let into your life. The biggest question out there is what is the "best" diet (or lifestyle)? There is no shortage of options these days.
Is breakfast really the most important meal of the day? Maybe it's less about when you eat but what you eat. Make sure whatever you put into your body in the morning is nutritious fuel for the rest of your day!
Everything you eat has calories, that's kind of the point. Your body needs calories for fuel! Calories are not the enemy! However, if you are eating more calories than your body can use or too many empty calories then yes you will likely gain weight. These are the reasons I no longer count calories.