good fortune vs boon

good fortune and boon both are nouns.

Word	Noun	Adjective	Verb	Adverb
good fortune	Yes	No	No	No
boon	Yes	Yes	No	No

As nouns, boon is a hyponym of good fortune; that is, boon is a word with a more specific, narrower meaning than good fortune:

Other hyponyms of good fortune include prosperity, successfulness, blessing.

good fortune (noun)	boon (noun)
a stroke of luck	a desirable state
an auspicious state resulting from favorable outcomes

good fortune (adjective)	boon (adjective)
	very close and convivial