BBC: Genesis 8:15-19
Then God said to Noah, “Go out from the ark, you and your wife, and your sons and your sons' wives with you. Bring out with you every living thing that is with you of all flesh—birds and animals and every creeping thing that creeps on the earth—that they may swarm on the earth, and be fruitful and multiply on the earth.” So Noah went out, and his sons and his wife and his sons' wives with him. Every beast, every creeping thing, and every bird, everything that moves on the earth, went out by families from the ark. – Genesis 8:15-19
What may be missed here is that for the time of the rains and Noah’s inspection of the land, God had been silent. The reintroduction of God speaking after His “remembrance” (Gen 8:1) should bring to mind the original proclamation of creation in God’s speech (Gen 1:3).
This time however there was not creation out of nothing. This textual theme is simply used to introduce the “new creation” that came from out of the ark in contrast to the earth “bringing forth” (Gen 1:31). Noah is commission with dominion as the “new Adam” (Gen 1:26-30) and his family is immediately incorporated.