1)
Having already written in Emor Vayikra, 23:44 "Va'yedaber Moshe es Mo'adei Hashem el B'nei Yisrael", why does the Torah repeat it here?
1.
Rashi: To teach us that when Moshe heard the Parshah of the Mo'adim on Har Sinai, he taught it to Yisrael, and as each Yom-Tov arrived, he taught it to them again.