No, you really don’t know a lot about it. You may have read the Bible. But your definition of who is and who isn’t a Christian leaves pretty much most Christians out. Do you really think you know more than people who have studied this for decades? By your logic, Catholics and Orthodox aren’t Christians. Do you really think you know more about Christianity than the largest and oldest sects of Christianity out there?
I’ll be blunt: nine years of Catholic school and three years at a Catholic college tells me you don’t know jack, kid. I believe I’ve suggested before you might want to see if you couldn’t get in touch with a Jesuit. They LOVE this kind of thing.
(Sola scriptura, the idea that Christianity is based on the Bible alone is not a universal tradition. You really, really should take a Biblical studies course, or a history of Christianity class if you’re interested in this.)