An overwhelming majority of what we eat is made from plants and animals. This means that composition of our almost entire food is chemicals from the realm of organic chemistry (carbon-based large molecules). Water and salt are two prominent examples of non-organic foodstuffs - which come from the realm of inorganic chemistry. Beside some medicines is there any more non-organic foods? Can we eat rocks, salts, metals, oxides… and I just don’t know that?
Interesting question. I had to look up the definition of food, the story version is it’s essential body nutrients.
You can synthetically derive some vitamins and things like that. But generally I can’t think of anything other than salt and water that’s not organic. You can start breaking down food into vitamins and minerals but that’s not really the intent.
I know animals will chew/gnaw on bones to get some calcium, maybe that.
Synthetic or not has nothing to do with whether something is organic or inorganic. That used to be the distinction 200(?) years ago, it is a bit outdated now.