extremely vs super

extremely is not a noun while super is a noun.

Word	Noun	Adjective	Verb	Adverb
extremely	No	No	No	Yes
super	Yes	Yes	No	Yes

As adverbs, extremely and super are synonyms defined as:

Other synonyms of extremely include deathly, exceedingly.

extremely (noun)	super (noun)
	a caretaker for an apartment house; represents the owner as janitor and rent collector

extremely (adjective)	super (adjective)
	including more than a specified category
	extremely large
	of the highest quality

extremely (adverb)	super (adverb)
to an extreme degree	to an extreme degree
to a high degree or extent; favorably or with much respect