What you eat while training is super important for performance and recovery.
Everyone is different, but you should make sure you eat healthy foods full of nutritious ingredients. My favourite breakfast before a short run is a bowl of Honey Nut Chex with almond milk. It's light and provides quick carbohydrates to fuel my workout.
For longer runs, I eat half of a bagel with peanut butter and honey. I've always stuck with Clif Shot Bloks for mid-run energy and electrolytes, but once I got into much longer distances, I was getting so hungry. I started adding in half of a Larabar about eight miles in — they offer carbs and protein and are super easy to digest.