new vs immature

new and immature both are adjectives.

Word	Noun	Adjective	Verb	Adverb
new	No	Yes	No	Yes
immature	No	Yes	No	No

new (adjective)	immature (adjective)
not of long duration; having just (or relatively recently) come into being or been made or acquired or discovered	not yet mature
unaffected by use or exposure	characteristic of a lack of maturity
(of crops) harvested at an early stage of development; before complete maturity	(used of living things especially persons) in an early period of life or development or growth
lacking training or experience	(of birds) not yet having developed feathers
original and of a kind not seen before	not fully developed or mature; not ripe
other than the former one(s); different
(often followed by `to') unfamiliar
having no previous example or precedent or parallel

new (adverb)	immature (adverb)
very recently