Sin is rebellion against God who created us to fellowship with Him.
Sin requires the shedding of blood - death.
Since God did not give up on us despite rebellion, He had to provide a way for us to escape death required for our sin.
So, He decides to be the sacrifice for our sin.
Jesus took our sin upon Himself.
Jesus died for us satisfying the requirement of the law.
So salvation is available but only through faith in Christ Jesus and coming to Him to receive His Grace through that faith.