As far as food you will want a high quality plain pellet such as Oxbow, Kleenmama's and if you can't find/get those brands then Mazuri 5664 is suitable. Stay away from brands found in stores/petstores as they have less than desirable ingredients including a harmful preservative in many called ethoxyquin. Among the bad brands are Hartz, 8-in-1 (owned by Hartz), Geisler, Kaytee, Nutriphase and others.
You will want at least 1 cup each of fresh (no frozen or canned ever) veggies for your pigs every day. This includes lettuce of any type except iceburg, bell pepper, chard, zucchini, 1 small/medium baby carrot per pig and cilantro. There are other veggies that you can use on a rotating basis but they aren't good every day foods due to either too much calcium, Vitamin A, phosphorus or oxalic acid. There is a sticky thread at the top of "About Guinea Pigs" called Common Misconceptions..., there is a post in there on what foods can be fed daily, every other day and weekly.
I don't suggest using a water bowl for pigs as you would be changing it every time you turn around. There are many creative ways to hang a water bottle.