Welcome to the forum!
While I don’t have any particular literature in mind for recommendation, I will personally lay out some of my views as best I can.
Most Bibles describe Genesis 3 as “The Fall of Man”… But it would be more accurately titled “The Exile”. God kicks Adam and Eve out of Eden, and sets a Flaming Sword on one end of it, to prevent Adam and Eve from eating of the Tree of Life and live forever. If they were created immortal then what would be the purpose of the Tree of Life, and why would God try to keep them from it? Hence, I firmly believe Adam and Eve were created mortal.
Along with this exile in chapter 3, we get yet another exile in chapter 4, with Cain getting exiled from Eden entirely, and banished to the Land of Nod. In Ezekiel 37, the prophet gets a vision from God known as the “Valley of Bones”. In this vision God shows Ezekiel a Valley of Bones whom, by the Word of God, grow sinews, muscles, and skin, and become alive once more. It even uses terminology such as “breathing life into them”. After the vision ends God says that these bones are the Children of Israel. From Ezekiel we further know that this after the Babylonian Exile takes place — hence we can infer a very important point. The Israelites equated “exile” with a form of “death”. If interpreting Scripture with Scripture is still a valise concept, I suggest that the phrase “in the day you eat of it thou shalt surely die” is used in the same sense as Ezekiel 37. The “death” they experience is the exile from the garden … Which plays out again in Cain to the Land of Nod.
This can help shape and broaden our view of “death” in Hebrew terms. The existence of physical human death before the Exile, isn’t a problem for me, theologically, because Law cannot exist lest God introduces it. He did that when he gave Adam the commandment in Genesis 2. If humans existed before the Law was introduced, then by that definition humans can’t be held accountable for what they do — they are amoral (in the biblical sense). And while one might say they were, in the biological sense, human — in order to be human in the biblical sense you have to have “the image of God”.
This admittedly, probably comes off as confusing, and even conjectural. But it took me awhile to start readjusting my modern mindset with that of a more ancient one — and we are all still learning.
I hope you enjoy yourself on the site.