This is such an important question for today because we know anything other than the true gospel will not bring salvation (Gal 1; 9.). It is the gospel of grace alone. This is the true gospel that brings salvation and is described in the bible from Genesis through Revelation, only. This is why the book of Galatians is so hard for many to understand, churches have fallen into the same trap as the Jews did, mixing grace and works.
Thankfully, God will not loose any of his people (John 6:37, John 10:5). If He intends on saving someone He will. But we have to trust in God alone and constantly compare scripture with scripture (1 Cor 2:13). When properly understood, we see there are no contradictions in Bible. This is further evidence the bible is from God as it took more than 1500 years and more than 40 scribes to complete it. Only God could have written it this way (I Thessalonians 2:13, II Peter 1:21). We must hold the position, "let God be true, but every man a liar" (Romans 3:4).
So, I believe the best one can do is pray God for understanding while approaching the Bible like a child, that is be willing to learn and not come thinking you know all the answers. We are actually told to pray and prove (or test) all things (I Thess 5: 17-21). Bring your questions to those you trust and if they say just trust us or dont worry as long as you stay with us youre safe or they dont provide satisfactory answers supported by scripture, or if you are told the bible is not 100% accurate then Id be weary of staying in that environment.
By nature, man is blind, and so the potential to get snared into a false gospel is exceedingly great. On the other side of the coin, God in His mercy can open our spiritual eyes, and then we see the truth. If He has saved a person that person will recognize a false gospel and turn from it (John 10:5). The environment in which God works is through prayful study of the bible (Romans 10:17). The Bible (OT & NT) is how we verify truth.
To God be the glory.