Just a thought
God made heaven and filled it with angels. Lucifer rebelled and fought with St. Michael. Lucifer and his followers were banished to Hell forever. God created Earth and man to live here as a test or trial. If we passed the test we would go to heaven, hence, we would replace the fallen angels. We would not be angels of course, but God would fill up heaven again. Adam and Eve had no original sin on their souls. The father of lies, Lucifer, tricked them and they sinned by going against God’s rule and taking from the tree of knowledge. Because of this we now have original sin on our souls from the get go. However, Baptism washes that away. The evil one is very jealous and envious of the people on Earth so he tries to get as many souls into Hell as possible to show God he is better than Him. Of course, no one is better than God! So God put us here on Earth to see if we love God or do we believe we are better than God? If we think we are better than God we go to Hell. If we love God, we go to heaven with a side step in purgatory to clean our souls of the sins we have committed from the times we listened to Lucifer. No one impure can enter the kingdom of God. Just a thought that we humans will take the place of the fallen angels and give glory and praise to God in heaven forever. This is one reason Satan is so envious of us and uses every trick in the book to get us to deny God.