What B'rachah did Aharon confer upon the people?
Ramban #2: Aharon raised his hands and blessed the people with a personal, unspecified B'rachah. 3
Ramban #3 (citing the Toras Kohanim): He blessed them with Birchas Kohanim, which Hashem commanded him to perform here on this one occasion. In Parshas Naso, Hashem instigated it for all the Kohanim to perform on a regular basis. 4
From where did Aharon descend?
Rashi and Targum Yonasan: From the Mizbe'ach. 1
Not from where he blessed the people, suggesting that the first half of the Pasuk and the second half are inverted (See Sifsei Chachamim).
Why does the Torah not mention that he offered the Minchah?
Moshav Zekenim: The Minchah was merely to be Machshir the Korban. 1
Moshav Zekenim: The Torah was concerned to mention only the Zevachim.
Moshav Zekenim: This is unlike what I explained that the Minchah was Nedavah!
QUESTIONS ON RASHI
Rashi writes that he gave Birkas Kohanim. This was before Avodah ("va'Yered me'Asos ha'Chatas
Moshav Zekenim citing Ri, citing Birkas Kohanim: Our verse is out of order. 1
Moshav Zekenim citing Ri: Birkas Kohanim precedes 2 Avodah of Haktarah of limbs. Birkas Retzei corresponds to Zerikas ha'Dam; this precedes Birkas Kohanim.