The advantage of this is there are allergists who work on permanently getting rid of food allergies. As far as I know for Celiac sometimes people who are perfectly off of gluten for ~7+ years will sometimes balance and their Celiac's will go away, but it's rare.
Celiac, like Type 1 diabetes, gout, lupus, and many other auto-immune disorders can only be managed, not magically cured.
Gluten intollerances are a different matter entirely, and can stem from over use of gluten enriched flours (think pizza doughs, white bread, anything using bleached flours, and anything that commercially needs more rise than the natural flour can provide).
Unfortunately, there is no strong consensus that gluten intolerance does or does not exist, and the best most folks without Celiac can do is a nutritional exclusionary screening. The real tell on it is more to do with what grains can or can't be used/tolerated when it comes to wheat sensitivity, gluten intolerance, or fodmap carbs.
Since then I've been preparing all my meals from scratch - I don't eat out much. Thankfully in Canada it isn't too hard to find GF ingredients, but I sometimes have to get creative. I generally try to discover new GF foods rather than eating GF "knock-offs" (eg. GF pasta, which is rarely good). Not all places in the world use wheat-based ingredients as much as in the west, so I try to look towards other cultures with different cuisines (for example, I learned to make onigiri which is really good as a snack).
I almost never eat food prepared by someone else because it's just too risky given how severe my celiac disease is. I'll often bring my own food or help cook if I'm eating at a friend's.