Plato’s dialogues are available in the Greek-English Loeb editions.
Burdet’s editions gives the Greek text with erudite notes.
The Online Library of Liberty (OLL) website gives the five volume edition of Plato by the great English Victorian Greek scholar, Benjamin Jowett. The scholarly apparatus is immense and detailed and there are fine introductory essays. The online version preserves the marginal comments of the printed edition and has links to all the notes and comments provided by Jowett:
The Dialogues of Plato, in 5 vols (Jowett ed.) | Online Library of Liberty