Visit a nutritionist- they should have lots of resources.

You poor thing. Check sauces, medicines, make up, lip balm, chewing gum, moisturiser, and anything else potentially ingested. It is in everything. (And oats are often processed with wheat and therefore unsafe).

Also; there should be a good range of cookbooks available in bookshops and the local library.

I agree with some of the other comments – I’d seek some help from a dietician or nutritionist..

There is such a wide range of foods available nowadays for this and many other conditions & allergies. There are also some great online forums you could join for advice, recipes etc from people who know their stuff.

A dietician/nutritionist should be able to provide support and ideas.
Also; there might be some good coeliac online groups that have resources and information.
The local library might have books on this topic with recipes, hints and tips and other useful information. Always worth sourcing the local library.

Have you looked at social media to see if there are any groups you can join. I have joined a few fussy eater ones for my daughter and this helps.

There’s a whole group of foods that is safe to eat, such as:
Fruits and vegetables.
Beans, seeds, legumes and nuts in their natural, unprocessed forms.
Eggs.
Lean, nonprocessed meats, fish and poultry.
Most low-fat dairy products.
Foods containing gluten (not safe to eat) aand for which you should seek gluten free options
bread.
pasta.
cereals.
biscuits or crackers.
cakes and pastries.
pies.
gravies and sauces.
Success ! It’s not that hard as nowadays there’s lots of substitutes on the market !