Joey jojo,
You are confusing a few subjects due to perhaps lacking a common frame of reference, that is all. But it can prove to be a stumbling block to comprehend what I am saying.
For instance, you mentioned that...
You seem to imply that a reason to believe in God is simply because the Jews exist due to the covenant with God.
I said Jews accept God as real, not that we BELIEVE in God.
Yeah, I know. That may not seem like something different to you, but there is a wide gulf in Jewish life between a belief (what one mentally assents to) and something that just is regardless of one's assent. Whether I believe it or not, you are real, right?
You see, Jews aren't keen on "belief," especially these days. What you are is defined by what you do, not by what you say you are or what you claim to believe in. Most Jews, even the most religious, will tell you that they don't "believe" in God. That's more a Christian thing.
Also no one, including Jews, are God's chosen-over-others. Each race and each person, religious or not, plays a chosen part unique to each. The "chosen" thing in reference to Scripture has to do with ancient language describing our part to play among all others. The Bible is a static picture of a time long past. We have different language and a different understanding for all this today.
And we don't follow Torah or accept the existence of the Patriarchs because the Bible says so. We followed Torah before we wrote the Bible. We have a separate history that we later used a bit of in the Bible, but our history came first. We followed Torah first. We wrote the Bible after Solomon's Temple fell. So you can't ask why our culture accepts all these things in the Bible as we were doing that before there was a Bible.
Plus, the Bible doesn't follow the historical view we have of ourselves. For instance, just read a Passover Haggadah. Notice how the story we tell of our deliverance on Passover night differs from what you read in Exodus. The Bible is the liturgical version, the Haggadah the traditional version, and there is a third historical one too.
There's a lot more to take in that would take you far off track from this site. I'm not here to make any Jews out of anyone or to recommend religion itself to anyone. Consult MyJewishLearning.com if you want to know more about Judaism.