Well, it requires years of studying and learning several languages, that's for sure, but you can begin with something very simple and fairly easy to do. All you need to do at minimum is to recognize something very basic but very very important about the canonized Biblical texts, and then proceed to read some ancient contextual literature you probably have not read before.
First you must recognize something very basic but very very important about the canonized Biblical texts. The texts of the Bible were written and canonized during definitive periods in the ancient Jewish/Christian past. Again for emphasis, that's "definitive periods in the ancient Jewish/Christian past."
We can talk about when these texts were written, but the JEDP theory approaches what is much more likely than that Moses ever wrote the Torah. Only evangelical scholars who teach for evangelical colleges who must sign doctrinal statements each year think differently (why the need for this if the evidence for evangelical scholarship is there in the first place, right?).
But back to my main point. These texts have a context. And they were written and accepted during certain periods of time in the ancient past.
I'll assume you agree.
Now think on this. We can easily compare these texts with the texts from surrounding cultures. There are OT Parallels such that it's at least understandable why someone would write a whole book called The Secret Origins of the Bible.
But there is even more than this to grasp and understand. There is something called Intertestamental Literature, the period of about 400+ years between the testaments. And with recent discoveries there are discoveries about other Christianities and their Scriptures, which Bart Ehrman has written about.
Now here's what you should do if you want to be what can be called an educated biblical scholar (rather than a backwoods evangelical). Read this comparative literature. Do you think the ideas in the Bible are new and revealed from heaven? Read this literature. Do you think the ideas in the OT were seeds that miraculously blossomed in the NT? Read the intertestamental literature. Do you really want to know what the earliest Christians thought about their Christianities? Read the early Christian literature.
You see, Christians take the biblical texts as if they are a divine history of their faith for the first millennium or more without attempting to discern the context for these documents. There is a discernible development to their intellectual history and it looks completely like the evolution of a faith not a divinely revealed one.
Here's a meager comparison. It would be like reading a history of the United States that was partially written during the Revolutionary War without referring to why early Americans revolted in the first place (i.e., the context), and partially written during the Stock Market Crash by a rich author, without any context as to what caused the crash in the first place.
There is a complete lack of historical perspective in the periodically written texts of the Bible. Add to that the extraordinary claims or "wonders" we find in it and there simply is no good reason to believe them.
They say the key to buying a home or a business is Location. Location. Location. Well, the key to understanding the origins of the Judaic-Christian faith is Context. Context. Context.