present vs here and now

present and here and now both are nouns.

Word	Noun	Adjective	Verb	Adverb
present	Yes	Yes	Yes	No
here and now	Yes	No	No	No

As nouns, here and now is a hyponym of present; that is, here and now is a word with a more specific, narrower meaning than present:

present: the period of time that is happening now; any continuous stretch of time including the moment of speech
here and now: at this time

Other hyponyms of present include now, moment, present moment, date, nonce, time being, today, tonight.

present (noun)	here and now (noun)
a verb tense that expresses actions or states at the time of speaking	at this time
something presented as a gift
the period of time that is happening now; any continuous stretch of time including the moment of speech

present (adjective)	here and now (adjective)
temporal sense; intermediate between past and future; now existing or happening or in consideration
being or existing in a specified place

present (verb)	here and now (verb)
bring forward and present to the mind
cause to come to know personally
deliver (a speech, oration, or idea)
recognize with a gesture prescribed by a military regulation; assume a prescribed position
formally present a debutante, a representative of a country, etc.
present somebody with something, usually to accuse or criticize
perform (a play), especially on a stage
represent abstractly, for example in a painting, drawing, or sculpture
give an exhibition of to an interested audience
give as a present; make a gift of
hand over formally
give, especially as an honor or reward
offer for others to consider