puppy vs young person

puppy and young person both are nouns.

Word	Noun	Adjective	Verb	Adverb
puppy	Yes	No	No	No
young person	Yes	No	No	No

As nouns, young person is a hypernym of puppy; that is, young person is a word with a broader meaning than puppy:

Other hypernyms of puppy include spring chicken, younker, youth.

puppy (noun)	young person (noun)
a young dog	a young person (especially a young man or boy)
an inexperienced young person