Not sure if this is a real question or a question to provoke our thoughts but..
If you actually read Genesis yourself and not listen to creation stories from others or Sunday school teachers blindly, you will know the answer.

In Genesis, God created the Earth and Adam and Eve (literal or not is up to your interpretation). There were 2 special trees: the tree of life and the tree of knowledge of good and evil. God forbid them from eating from the tree of knowledge of good and evil but did not say anything about the tree of life (so technically they are allowed to eat it and live forever).

What Sunday school and Christians miss out is the tree of life and only thought there is only one tree. It was only after they are the fruit of the tree of knowledge of good and evil did God forbid them from eating from the tree of life by placing a cherubim with a flaming sword to guard it and cast them out from the Garden of Eden.

If you are Catholic, the Eucharist (flesh and blood if Jesus) is the fruits of the tree of life. Think about it. Jesus died on a wooden cross (cross made out of wood) therefore it is like a tree and when Catholics eat the 'flesh' it is the fruits of the tree of life. In John 6, Jesus claims his flesh is the bread of life and Jews joked at him by saying how can this man give us his flesh to eat.

v21: I don't think it has anything to do with 'born again'. The term born again is being thrown around and used out of context. Here Jesus just means that many Christians claim to be Christians but do not feed the hungry, clothe the poor etc. In other words, just being 'Christian' just for the recognition akin to the Pharisees. This is common especially in a lot of mega-churches you see today where people join for for friends, to socialise or find business partners (see City Harvest Singapore scandal)

v22: Another common theme especially in Protestant Christianity is doing fake miracles as proof that God exist (i.e. healing blind/deaf). If this is true, these preachers are better than doctors and they should have contributed their powers to hospitals instead. Some even claim to have went to hell and back, elected by God, etc (see Phillip Mantofa) or preachers who do televangelism but do not live the life of Christ (see Benny Hinn).

It is best to interpreting by reading the whole chapter and not taking it out of context.