You don’t. You need to find all of this out for yourself, PRAY and ask God for help. Because even if everything I’m telling you that I believe to be the Truth with all my heart and soul someday ends up being wrong, there is still only ONE Truth. If I’m right I stand to gain everything: eternal life! If I’m wrong I lose nothing.
But don’t just stay in limbo, read more about all of this and see for yourself. Start with these if you haven’t read them yet: