This is a very hard question, because there is so much gluten that hides in foods, and there are many gluten free alternatives that they have made now to replace some of the gluten containing foods. But I'm going to try and help you out a little.
You can't eat Bread or Pasta unless it's Gluten Free. No cookies, pastries, pies, cakes, donuts, pretzels, cereals, anything made with flour (unless they are special and have been made gluten free). You will have people tell you that White Bread doesn't have wheat in it, IT DOES! Most Soy Sauce has wheat in it, so you have to look for wheat free soy sauce or Tamari. So this really limits going out for Chinese. Going out to eat is hard until you are used to what you can eat or unless the restaurant has a Gluten Free menu.
This seems very limiting, but there is a lot of Gluten Free stuff out there. And you can eat all vegetables as long as they don't have a sauce that was made with wheat (like a hollandaise), and some spice mixes have wheat in them, don't ask me why! Just check the label and if you are still unsure, call the number on the jar and ask them. I've done this in the store.
You can eat any meat. Except lunch meat, they often have things added. There are gluten free lunch meats, you just have to look. Boars Head is one of them.
You can eat most cheese unless it has mold in it and you can eat most of those. They used to start all Blue Cheeses mold on bread so we couldn't eat it but now most dairies don't start the mold on bread. You just need to find out. All hard cheeses are safe.
You can't eat Malt, unless you know it's not barley. Most is barley. You can't have malt vinegar. But most other vinegars are fine, some people are scared of vinegars, but just check the ingredients.
You can have rice, potatoes, root vegetables, and alternative grains like quinoa, kamut, millet, buckwheat (no buckwheat is not wheat).
If I can help you in any way please let me know.