We don't use article before nouns that we can't count. You can't count past.
Let me give you some examples from http://grammatikk.com/pdf/UbestArt.pdf
Uncountable nouns are often food and drinks. Here we often write the word without article even though we have an adjective.
"Nå skal vi drikke melk." Now we are going to drink milk.
"Har du tid nå?" Do you have time now?
"Det er pen snø ute." It is pretty snow outside.
Some types of food we can count. Then we can use article, but it gets another meaning: "Jeg spiste fisk." (Kategorien fisk: Jeg laget mat av fisk.) I ate fish. (The category fish: I made food of fish.)
"Jeg spiste en fisk." (Kvantitet: Jeg spiste en hel fisk.) I ate a fish. (Quantity: I ate a whole fish.)
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