May I safely assume you have some device to access the Internet -- like a smartphone, tablet, or computer? Assuming yes, may I assume it came with an instruction book?
Quick. Who wrote that? When? How? Did the writer get it all right, or is there debate going on about some aspect of it? After all, how can you possibly trust a book when you don't know all that stuff, right? (Yes, I am sarcastic. Why do you ask? lol)
How did you trust your textbooks back in school? How do you trust sites online? Do you investigate them too? Do you then research who the author is? And, yes, I'm not completely nuts, there really does come a time when it's time to research all this stuff, but, really? Why this book, without doing the same thing to all other reference books you've ever read?
Have you ever studied anything else that you were curious about just to study it before? (I'm also assume you've done that too.) Ever pick a subject that you weren't completely caught up in believing even when you started?
For me, it's dinosaurs and older hominids. The stuff fascinates me, probably since I grew up near the site where they found the first full skeleton in America and actually finally figured out there really were some huge reptiles living in America before Europeans ever came here. But, yo, I'm a creationist, so obviously I'm still skeptical. That's fine. Not like I can't believe in dinos and earlier forms of humans, right? But I do read with an open mind, let it sink in, don't have to spend much (usually any) time figuring out who the writer was or why he/she wrote, and can still think on my own after I'm done.
Tell me you can't do the same thing.
So really? Why are you wasting this much time researching all the background to every book you're reading in the Bible just to settle on if you should believe it? Not like that's needed, but here you are doing that anyway.
Just seems to me you're spending an inordinate amount of time making up reasons to skip what you already promised you do -- read the Bible.
Lots of folks have been telling you how to read it, who you need to decipher it, what you need here and what you need there, but despite all that, you said from the beginning you just want to read it. Okay? Read it.
I trust in three things right now:
1. You're smart enough to read it all the way through.
2. If God is going to do something with you as you read it, God's going to do something with you as you read it.
3. I've read enough reference books written by fallible man to know Man is capable of writing stuff without errors once in a while. If something has a bunch of errors in it, the writing won't make a big splash and won't continue to be read. If it's relatively error free, the writing will stick around for a while. (The Bible is, at least, 1900 years old. Some of it is much older than that, and it's still the all-time best seller.)
I have no idea if God will get through to you or not, but whatever plans he has, he'll do. You're just supposed to read it. So, seriously, who cares if there is a secret gospel of Mark or not? Kind of like trying to figure out Dobby's genealogy before reading Harry Potter and The Goblet of Fire. Who cares until you actually read it and that's not part of the story anyway.
And, that's just me knowing I can come up with just as many excuses not to do something I set myself to do as you can. lol