Leaving Naples early morning for Milan, does Alitalia serve breakfast?
I assume you refer to economy class. I don't know about Naples-Milan, but my experience is that in most national flights Alitalia serves only a minimal amount of food and beverages. I expect to see a limited selection of beverages (tea, coffee, water, coke, and orange juice), and a very small snack (sweet or savoury at your choice), like a small package of biscuits or saltines.
So, something insufficient for a typical Italian breakfast, and very far from a continental breakfast.
Also, don't expect to get newspapers.
Alitalia has undergone severe cuts in the last years, and the quality of service has been affected negatively, especially when it comes to these small perks.