I buy whole wheat tortillas, grate a little cheese on top (cheddar or jack, usually), microwave it, then roll it up and eat it. Super fast and reasonably healthy.
A minute longer: toast an english muffin with a slice of mozzarella on top (you can tell him it's like a pizza!).
Van's Power Grain frozen waffles have 10g of protein. I'm under no illusions that they are super healthy, but it's better than sugary cereal and I bet an easier sell than eggs.
https://www.vansfoods.com/our-products-waffles# These are tasty.
Kashi also has some high protein cereals, not sure if he would go for them. I like Go Lean Crunch if I add a banana or some berries, but I'm not sure a teenage boy would go for it.