I've been non-cook for years now. My preferred staple is plain rolled oats, either the 5min or 1min variety. The 5min and 1min is SUGGESTED cooking time, but oats does not REQUIRE any cooking, as is proven by the fact that most people eat granola uncooked. Avoid the instant variety, since I believe these are processed somehow. Plain rolled oats is oat berries, with the outer kernel removed, then rolled with steel rollers, then lightly steamed to pasteurize and aid shelf longevity. It is the only true whole-grain cereal that is widely available in ordinary grocery stores in the United States and Europe. Oats contains adequate protein and plenty of fiber, so that you can eat it day after day without any nutritional problems, provided you supplement with a multi-vitamin (especially Vit C and the B vitamins).
Bulgar wheat, buckwheat groats, rolled wheat and rye and all similar in preparation and nutritional content to rolled oats, but not as widely available. All of these grains can be eaten uncooked (just let them soak for about 5 minutes), since the preparation involves enough steaming and crushing to make the grain fully digestible by the average human digestive system.
In Europe, couscous is widely available. This is another food that can be eaten raw (after soaking for 5 minutes), regardless of what the instructions say. However, couscous is a poor nutritional choice, about the equivalent of white bread. In particular, it has no fiber. I once got so sick I had to lubricate my fingers and go poking around to get things moving again--not recommended...
It may be possible to eat grits and cream of wheat raw (black bears will eat them that way just fine, thank you), but they certainly won't taste good. Like couscous, they are very poor nutritional choices.
Most dried cereals are also poor nutritional choices. They may say they are whole-wheat, but they are actually mostly refined wheat with some food coloring and sugar thrown in.
I've tried eating GORP day in and day out and it soon sickens me. By contrast, oatmeal is a very boring food, but eventually I get quite comfortable with it. It's like plain water. Nothing exciting about drinking that, but it provides what your body needs. I usually finish off my oatmeal meals with some sort of salty delicacy, like a piece of cheese or dried sausage. This delicacy makes me forget how boring the oatmeal was.
I make mostly dry camps and so never have a surplus of water. To clean my bowl after eating, I just pour in a little more water, then swish around, then drink, then repeat until the bowl is clean. Do this immediately after eating, before the oats has a chance to harden.
If you want tea in the morning, you can just drop a tea bag into a mug of cold water in the evening and then leave it overnight to steep, then squeeze the bag in the morning to get all the drops of tea out. Works quite well. Get a mug with a lid to keep crud from blowing in during the night. Instand coffee might work the same way, though I've never tried.
If you need some sort of container to prepare either oats or other grains, and perhaps tea as well, I recommend a metal mug, like the MSR Titan Kettle. That way, you can yogi someone else's stove to sterilize your mug now and then. Plastic weighs just as much and is not nearly so easy to clean and sterilize.
You'll probably pack your oats or other grains in an O.P.Sak or the equivalent. Bring along a small 2oz plastic scoop to transfer oats from the plastic sack to the eating bowl. If you try to pour the oats out, you'll spill them. If you dip your bowl into the oats, you'll possibly transfer moisture into the dry oats (such as when you're going for second helpings) and this can cause the oats to become moldy.