Congrats! We have an African Grey too and a Blue/Gold Macaw.
As for feeding, choose a high quality seed mix or pellet form that is always available. But the same things apply with birds as we've learned it does keeping fish. You want to give a varied diet of other healthy items they just won't get from commercial food alone.
Birds naturally lose and replace a lot of feathers. Since those regrow all the time in between molts, birds need a good amount of protein and calcium. So keep that in mind when it comes to treats.
On a daily basis, our birds get a serving of lots of things, depends on what we have in the fridge this week.... 3 or so kinds of raw green veggies (cucumber, broccoli, bell pepper, brussel sprouts) -- 1 or 2 yellow/orange veggies (squash, carrots) -- some kind of raw fruit (apple, orange, strawberry, banana, mango, peaches, whatever). Keep in mind that cherry pits and apricot pits contain toxins and they may crack that open. They also get some kind of lean meat, or cheese, or maybe a hard boiled egg or scrambled eggs. Peanuts and other nuts are always a treat. There's lots of other things you can give them like Puppy Chow (contains extra calcium) or other doggie biscuits.... whole grain or vitamin enriched breakfast cereals. Mine seem to like Cheerios, Crispex, Granola types, and Chex.
They really like cooked foods too... particularly something still warm. So I pretty much eliminate grease and salt as much as possible and let the birds have a dollop of whatever we're eating that day..... mashed potatoes, pasta, and so on. You'll want to stay away from the obvious no-nos like chocolate, sugar, salt, grease, caffeine...
