Half a cup of oatmeal(serving size) mixed with 3/4 cups reduced fat vanilla soy milk and a couple drizzles sugar free maple syrup(serving size is 1/4 cup)
4 egg whites mixed with one slice low moisture part skim mozzarella cheese

Roughly 380 calories and a lot of protein!

Is this a good breakfast?

Are you following the nutrition guide at all? You are still in the first 30 days, right? If so, you should be eating HIGH protein, LOW carb. As in 1 serving of carbs PER DAY. Oatmeal is FULL of carbs. A better breakfast for phase 1 would be (depending on which calorie level you are on) 8-10 egg white omelette with low fat mozzarella cheese, and 2 slices of turkey bacon.
Your snack is ok, and lunch/dinner should follow the same suit as breakfast. More meat and veggies, no sauces, bread or potatoes.

Oatmeal doesn't come in to the meal plan until Phase III.

Oatmeal is listed in the phase 1 diet. It says you can have 1 cup. I realize Im a beginner but I think that is a great breakfast. I have been eating either 1 cup of oatmeal or 1 cup of cereal in the morning with a piece of fruit. I think your doing great....but what do I know. Good Luck!!!

Im trying to eat what kilimatic from youtube ate throughout his whole 90 days just for the fact that he got AMAZING results. We're both level 1 and everything and im on day 40.

Is a half cup of oats per day really gonna mess me up? geez

And yeah I dont have the nutrition guide