I understand where you are coming from, however, this is a complicated topic that ties into the idea of free will and predestination. I will try to explain the concept I believe as best I can. To begin this explanation, I must set the stage. To do so one will ahve to accept the following statement: As humans, I believe we have free will.
Adam made the mistake, and brought death into the world. As his descendants, we are brought into a world of death created by the first downfall of Adam.
Regarding your first statement, the Jewish religion was established as a way to go to heaven, however atonement was required for every sin in the form of sacrifices, in order to be a righteous person. We know people from the old testament went to heaven because of the example of Elijah in 1 Kings 18.
Jesus was sent down to earth as the ultimate sacrifice for all of our sins. In order to reap the benifits of the sacrifice, similar to the way they were in Judaism, we as Christians instead only need to accept the sacrifice made for us, instead of needing to sacrifice animals like the Jews.
Adam was not a sacrifice, he made the first mistake.
So to accept Jesus is not the same as to accept Adam, as implied in your response. I apologize for any misintepriation, but based on the statements i have presented, your statement would be considered a false analogy.
An attempt to simplify the statements I have made:
we as humans are born into a world of sin because of adam
we do not deserve forgiveness period but we were given a chance through salvation
to do this we must work for it even though there is technically nothing we can do to earn it
to get back to God, we must follow his instruction
Jews had to make sacrifices for their sins to get to heaven
we know there was heaven for Jews because of the story of Elijah rising to heaven
Jesus made the ultimate sacrifice
we as Christians no longer need to sacrifice
But to receive blessings caused by Jesus's sacrifice we need to love and accept him
I hope this helped explain my point of view! I'm willing to work a bit more to put it into a more organized thought if necessary.