Was Jesus Crucified for Our Atonement?

Wondered about the following questions ever???? Did Jesus (PBUH) die on the cross, as the Gospels mention and the contemporary Christian sects agree? ?? Assuming that Jesus died on the cross, was he crucified to atone us and humanity? ?? What is the salvation from; is it from the Hellfire or from the world's troubles and miseries? ?? Is it a salvation from our parents' (Adam and Eve) sins only, or all of our sins? We will answer these questions objectively, logically, and scientifically; searching the pages of the Christian Holy Bible, taking our minds, our instincts and our reasoning as the judge , considering the professes of the history and the wisdom of Christianity's wise men as evidence.