young vs brute

young and brute both are nouns.

Word	Noun	Adjective	Verb	Adverb
young	Yes	Yes	No	No
brute	Yes	Yes	No	No

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

Other hypernyms of young include animal, animate being, beast, creature, fauna.

young (noun)	brute (noun)
any immature animal	a living organism characterized by voluntary movement
young people collectively	a cruelly rapacious person

young (adjective)	brute (adjective)
(used of living things especially persons) in an early period of life or development or growth	resembling a beast; showing lack of human sensibility
(of crops) harvested at an early stage of development; before complete maturity
not tried or tested by experience
being in its early stage
suggestive of youth; vigorous and fresh