We were thrown into the world of food allergies almost 3 years ago (dairy, soy, and eggs). Our child did need an endoscopy to rule out another condition, which I wasn't super excited about (for obvious reasons!), but the entire procedure probably only 15min total, which includes us being called back to recovery.
Your child will read his cues from you - we just don't make a big deal out of it. I have a stash of "safe" cupcakes and pizza (wrapped in individual serving sizes) in the freezer along so I'm ready for last minute parties or special events. He brings his own lunch, snacks, and milk to daycare. I try to match his lunch to what the other kids are having, but it doesn't always happen. The teachers know to give us a heads-up if there's a birthday or other special event where the kids are getting a "special" snack so that I can send in something for him. We also keep a container of safe snacks in his classroom and refill as needed. He never feels left out - he will ask if something has cow's milk or soy if there's food at a party he can't have. He knows it will make him sick if he eats something that contains one of the things he's allergic to.
I don't make anything at home that he can't eat as a main meal. If we're all eating together, it's safe for him. I've found (with a few exceptions) that it's just easier for us to only keep foods in the house/make food he can eat. This way there's no confusion, especially when leftovers are in the fridge! There are a lot of gluten free products in stores as well as blogs devoted to gluten-free cooking and baking. I know it seems a little daunting at first, but it does get easier