Here is what the Jamieson-Fausset-Brown Bible Commentary, written in 1870 (before general relativity or modern cosmology) says…
The Old Testament
THE FIRST BOOK OF MOSES, CALLED GENESIS. Commentary by Robert Jamieson
CHAPTER 1
Ge 1:1, 2. The Creation of Heaven and Earth.
1. In the beginning—a period of remote and unknown antiquity, hid in the depths of eternal ages; and so the phrase is used in Pr 8:22, 23.
God—the name of the Supreme Being, signifying in Hebrew, “Strong,” “Mighty.” It is expressive of omnipotent power; and by its use here in the plural form, is obscurely taught at the opening of the Bible, a doctrine clearly revealed in other parts of it, namely, that though God is one, there is a plurality of persons in the Godhead—Father, Son, and Spirit, who were engaged in the creative work (Pr 8:27; Joh 1:3, 10; Eph 3:9; Heb 1:2; Job 26:13).
created—not formed from any pre-existing materials, but made out of nothing.
the heaven and the earth—the universe. This first verse is a general introduction to the inspired volume, declaring the great and important truth that all things had a beginning; that nothing throughout the wide extent of nature existed from eternity, originated by chance, or from the skill of any inferior agent; but that the whole universe was produced by the creative power of God (Ac 17:24; Ro 11:36). After this preface, the narrative is confined to the earth.
Heavens is plural and is speaking of only the physical heavens and does not include the creation of the realm of God. Our physical heavens are just a dot in Gods heaven (realm).