God can save people in all three branches of Christianity (Catholic, Orthodox and Protestant) but Protestants have a fuller understanding of the gospel that gives them a better chance of entering a saving relationship with Christ. God cannot save anyone in Judaism as they reject Christ as their savior. Jews need to come out from that corrupt system to experience Salvation.
Though I doubt your ability to understand anything that is outside of your worldview, I will try to explain something very basic to you.
The Christian idea of "Salvation" is linked with the Christian concept of Sin, and specifically "Original Sin". Men need to accept Jesus in order to be "saved" from the consequences of Original Sin.
But those concepts are
Christian. Jews don't have Original Sin. We don't need to be "saved". For us salvation is national salvation, as appears in the OT, not individual salvation.
To call God's own instructions to the Jews a "corrupt system" is absurd. It is God's system for us.
It was never meant for non-Jews. The history of early Christianity is that of an originally Jewish sect that broke off from Judaism. Once it became a Gentile religion, it rejected the Law, and over the generations, turned God's rules for the Jews into a negative thing, since it had to separate itself from the religion of the Jews.