Do you have to
describe each noun
in a sentence?

No, you don't have to. The noun can stand by itself and it will be perfectly fine if its mot described. For example, proper nouns don't have to be described (Mary, Georgia, Barcelona...) . Common nouns on the other hand are mostly described so that the reader knows exactly what we are talking about.

Example:

Lilly took the red rose and placed it in her long, silver hair.

But, if we take out the adjectives (words in bold), the sentence will still work. The only difference is that we won't have a clear picture of what the person wrote.

line a --> main

line b --> young

line c --> atitude

could you provide an image?