There is no magic tricks on the eating, sadly. I have found when my kids are dragging through our morning routine, that me being ready and able to completely focus on them helps a lot. So I get up before them and get dressed, brush my teeth etc. Then when I wake them up, I stay with them in their rooms helping them get dressed. Even though they can both dress themselves, the extra attention from mom helps smooth some bumps. And it makes it more likely there are some mornings they will be independent.
I have one kid who is starving in the morning, and one who is not. I have to prod one to eat, but it's not easy. I try to get him totally ready while he's sitting there spaced out. So even putting on his shoes. Then he can take bites up until the minute we leave the house.
If he's in preschool, there's a good chance he has another breakfast, or at least a morning snack, coming soon so try not to worry about a full breakfast too much.