Since I'm on an iPhone I'll try to keep this brief. But at the time of Adam and eve man needed nothing. Everything he and the world needed was supplied by God. The bible states that God is light and that Jesus is the light of the world. You ask "what is evil"? Evil (darkness) is the absence of light (God). Think about what would happen if the sun stopped shining on the earth...that would cause a chain reaction of things dying off on the earth. What is lacking in nourishment would start towither away and rot....basically DIE. THAT is how "original sin" effected the earth. A slow and sure death. The bible says "the wages of sin is death, but the gift of God is eternal life through Jesus Christ our Lord.
Sin not only affected our spiritual well being but everything in the natural world. The devil lied to Eve when he contradicted what God told her. God told her that she would die but the devil stated that she wouldn't die but her eyes would be opened up. The fact is they didn't die an instantaneous physical death. But the process of death did start....not only for their bodies but for everything within the known universe. They chose the opposite of Light and instead chose the dark (where there is no nourishment).
By the way, Lilith was not real. That's a made up story to throw a curve to the Truth. It's no different from those who said Jesus never died but got married to Mary Magdeline and had kids. What a neat and convenient way of thwarting faith.