Moses 5:4 tells us that Adam and Eve offered prayer after they left the Garden of Eden:
And Adam and Eve, his wife, called upon the name of the Lord, and they heard the voice of the Lord from the way toward the Garden of Eden, speaking unto them, and they saw him not; for they were shut out from his presence.
According to Genesis 3, after Adam and Eve ate from the tree of knowledge, they heard the voice of the Lord God walking in the garden, and they hid from Him. Adam's first words to God expressed his shame and fear, as he was naked and felt guilty for his disobedience.
This moment is often considered the first recorded prayer, though it is more of a dialogue than a traditional prayer.
The first time Adam talked with God and expressed repentance and asked for forgiveness
"Then Adam wept and said, 'Lord, my God, you brought me to this land and allowed me to fall into this sin. Drive me not away from your face, but let me return to the dust whence I was taken.'" — The Life of Adam and Eve (Apocalypse of Moses), Chapter 10
The Life of Adam and Eve (also known as the Apocalypse of Moses): This prominent apocryphal text provides a vivid and detailed account of Adam and Eve's lives after their expulsion. Here, they engage in intense acts of penance, including lengthy fasts and immersions in rivers, explicitly to seek God's forgiveness and mercy. Eve, in particular, takes much of the blame upon herself, and Adam expresses profound sorrow and regret for their transgression. God does respond with comfort and promises of future redemption.
The "Prayer of Adam" in Sefer Adam refers to a supplicatory text attributed to Adam, found in medieval Jewish mystical literature, particularly within Sefer Raziel HaMalakh. This prayer is described as Adam's plea for forgiveness after eating from the Tree of Knowledge, where he apologizes for heeding Eve, who was deceived by the serpent. According to Sefer Raziel, God sent the angel Raziel to teach Adam spiritual laws and knowledge post-Fall, and the prayer is part of this revelation. It appears in Book Six of Liber Razielis, an expansion of Sefer haRazim, and was notably referenced in German Renaissance magic, including by Johannes Hartlieb and Johann Reuchlin