The true gospel is to turn from your ways to Yahweh's ways, as detailed throughout the Torah and expounded upon by the Messiah.
The Torah gives 633 commandments to be followed lest we cheese Yahweh off and he smites us. Jesus said he didn’t come to destroy the Law or set it aside but to fulfill it. I recently read that what he meant by fulfill was to live up to it, to be a shining example. Yet, and as much as I think Jesus is a cool dude for much of what he taught, he didn’t abide by many of them. There are no reports of him making the required sacrifices, he worked on the Sabbath, he refused to stone the adulterous woman. So, I don’t know.
Salvation is a gift of grace freely given by the Creator for all those who seek Him in truth and recognise that Yeshua is indeed His Son. However, thereafter we are to walk in His ways. Not to keep salvation but to honour Him in our obedience. We're not to continue sinning or go by modern Christianity's definition of what is and isn't sin - but be led by the Word and Spirit.
So even though I’m not “Christian”, but I believe Jesus existed as a teacher, prophet, messenger, sage, guru, yogi, jivanmukta (someone self-realized and “liberated” while in the body),
maybe even
aṃśāvatara (anshavatar, a partial incarnation, but I’m iffy on that), am I saved according to Christian teachings? We’re all children of God, so that part goes without saying.
If I live my life being devoted to (my image and view of) God to the best of my ability and with all my heart, soul and strength; live as righteous a life as possible; help and love others (that love others part is a challenge at times); don’t hurt others, don’t steal, kill, commit adultery or worship idols; if I hope that on my deathbed or as that tractor trailer is bearing down on me I remember God, am I saved according to Christian teachings? What else do I need to do?
If this is correct, then almost 2 billion Hindus, Sikhs, Buddhists, Jains are theoretically saved per Christian teachings. It should work even removing Jesus from the equation because they simply don’t know of him but have their own version of a teacher of his caliber. The word ‘savior’ isn’t used, but if it means being saved from ignorance, unrighteousness, and darkness by those teachers then it’s as good a word as any.
This is what makes me wonder why Christianity is so special. Gandhi (whom I think is neither wholly a hero nor wholly a villain as some people paint him) said
“After long study and experience, I have come to the conclusion that [1] all religions are true*; [2] all religions have some error in them; [3] all religions are almost as dear to me as my own Hinduism, in as much as all human beings should be as dear to one as one's own close relatives. My own veneration for other faiths is the same as that for my own faith; therefore no thought of conversion is possible.”
*My addition is that they are true for their followers. I think he did say that elsewhere.