Absolutely! Just because the ship arrives at 7am doesn't mean you'll be able to leave at that time. It is usually 60-90 minutes minimum before the first guests are cleared to debark.
Breakfast will be available in the main dining room and in the buffet restaurant. I strongly urge you to use the dining room, since it won't have frantic passengers rushing around and you'll have a nice sit-down breakfast as one of the last memories of your cruise.