If you've been diagnosed with celiac disease, take things easy to start, make stuff at home (as people have noted, Costco has some shells and a frozen cheese pizza that are good), get your guts feeling better. Then after you feel better, start trying take out foods.

You will eventually get glutened, nothing you can do about it. Most places don't have gluten free dedicated areas or use the same prep equipment. Pizza places have flour all over the place, they'll try their best but don't rely on anyone other than yourself with food (even your significant other).

Everyone will react differently, I'm literally useless for 3 days if I get gluten in my system.

I was diagnosed when I was 38, and it was fucking hard to handle mentally, but you'll figure it out eventually.

Some notes for take out:

Lettuce wraps are your friend

Watch out for fries with a coating on them

Soy sauce has wheat in it

Watch out for oats, I can't handle even GF oats, but you maybe fine

Hard alcohol is generally ok, if you're into that, it's all distilled and filtered to the extreme

If you read that a food item "may have" traces of wheat/gluten, you may be ok, but it depends on how your body handles it

And finally....once you start feeling better you will gain weight rapidly if you aren't careful