For instance, you can correctly say "I want bread." That isn't wrong the same way "I want phone" is wrong. This seems to apply to most foods, but I can't figure out what the rule is.
I want fish.
I want water.
I want coffee.
I want meat.
I guess these are categories, rather than specific things? Similarly you could say I want red if picking a color for a wall.
I'm not sure what the rule is for someone learning English, how would they know which words this applied to? I also don't know the term for such words, making it hard to look up.