OK. So, I'm a Christian. I first became one around the turn of the century, when I was in my late 40s. I'm now 71.
I, too, struggle with the many concerns expressed elsewhere in this company as well as on the internet. I think my understanding of the Bible and of Christianity is "correct" (but I've been called blasphemous and representing the Devil, so be warned). If this gets too ugly, maybe the admin can just shut it down.
So, here's my take (my journey). I'll introduce different aspects of my beliefs so that it can be discussed separately, as they are all controversial.
The first part is, Does God exists? Firstly, the question presumes the Christian God. Although it may include the Jews and Muslims, I will exclude them from my discussion mainly because I don't know much about their religions. There is an interesting passage in the beginning of John's gospel which says that (John 1:1 ESV)
[1] In the beginning was the Word, and the Word was with God, and the Word was God.
The interesting bit about this is that the Word is in Greek, logos - the root word of biology, psychology, etc., meaning reason or logic. The link here is to Stoicism, where the Greeks didn't so much believed in God but recognised that there's an underlying logic to human nature, just as there's an underlying logic to science (which is fundamentally an investigation into the laws or logic of nature).
The Greeks, esp. Stoics, believed that there's an underlying logic to human nature and that logic is called Natural Law, and it involves choosing Virtue over Vice. If you put aside the idea of God as "old man in the clouds", you may agree that we do have this human nature and that we should choose virtue over vice. If you agree, you already believe in God.
Man, humans, are very inquisitive. Just look at what we've learned in a very short period of time. Just look at what we've invented, it's truly a wonder.
Part of that are some pretty deep-rooted things: Where did we come from, what is conscience, where did the universe come from, and how did it start, etc.
Ancient man didn't have all the advantages we have today, and while they definitely weren't simply apes hiding in caves, they didn't have the benefit of generations of learning and discovery that we have today. Sometimes they did what made sense to them, such as worshiping the Sun as a God because hey, it made the grain grow! Or they would look at the stars, see shapes, and think they were meaningful, etc. They answered things given the, relative, limited set of data they had.
That didn't stop them wanting to answer these fundamental questions, and for much of the world that ended up being a singularity. That singularity is known as a God. At the same time, societies were growing both in size and sophistication, and they quickly learned that there were customs, and norms that were needed to keep everyone safe. We're a social animal, we like to stick together. We recognize what makes, and what breaks. These things got codified into the law, and norms, of the day.
Through the years, as man learned how to communicate with writings and drawings, these things were recorded. One of the books is a collection of stories that attempt to explain where we all come from, how we should live, and whom we should worship. You might call such a book, The Bible. The Bible isn't a book simply about God, it covers a lot of territory from historical events to temptations, philosophy, and the function of society. As such, it's one of the great works of man.
The issue, it seems to me, is whether one takes what is written literally, or not. And it's not easy, because you can't simply say "the Bible is all rubbish", because there are some historical facts in there, rules and laws we recognize, etc. No matter what, some of it has value. Which is why my own brain says that the value of the Bible and its teachings can be separated from the question of if there is a God. Even if there's not a God, a lot of what's there is important.
I don't think it's possible to know if there's a God. Not 100%. Just like, at the moment, we can't know what happened before the Big Bang (if there even was such a thing). We simply don't have the data. We have ideas, concepts, and some experimental work - but no definitive answers. Which is why we rely on faith.
We all rely on faith to an extent, I think. For example, I have a strong belief that there is life on other planets. We haven't found it yet, and I'm not convinced they're visiting us. But I do believe it's out there somewhere. I can only base that on blind faith, because we have zero evidence. Other people have faith in a God. That's a hurdle I can't get over. The answer for now must be - we don't know.