To the dear questioner, you were aiming in the direction that Rabbi David Nisani writes in his book According to the Plain Meaning: that it is indeed possible there were additional human beings referred to in chapter 1 of Genesis, whereas chapter 2 focuses on the story of the Garden of Eden and the creation of Adam and Eve, who were a kind of chosen pair among humanity for the role of guarding and working in the Garden of Eden.
(This also resolves the question of how Cain built a city if there were barely any people according to the approach that he and his family were the only ones in the world, and likewise his fear that they would kill him.)
However, this interpretation does not fit with the saying of the Sages, “Therefore man was created alone,” but the gates of answers have not been locked.. 😉

With God’s help, 4 Adar I, 5784

By the time Cain and Abel quarreled, 20–30 years could have passed until they matured and acquired a profession, and by the time Cain started a family, several more decades could have passed, during which Adam and his wife could have had sons and daughters, and later grandsons and granddaughters.

With blessings, Fish”l