Cain: Adam and Eve's First Child
Adam and Eve's first child was Cain, and Eve named him confessing that she had gotten a man with Yahweh's help. The same passage records Abel's birth and marks the brothers by their work, setting the stage for the offering and murder that follow.
Who Was Cain's Mother? Eve in Genesis 4:1
Genesis 4:1 names Cain's mother as Eve, the woman who conceived and gave birth and who spoke of the child as help from Yahweh. The verse answers the question directly rather than leaving it to inference.