These are the prime questions that motivated man to create a god. The human brain developed to survive. Man's curiosity is what made him successful in competing in a dangerous world. But there is a cost. Man's curiosity also drove him to ask the two afore mentioned questions. These nagging questions plagued him. They begged to be answered. Eventually, one of the men (probably seeking a higher ranking position in the small band) decided he would invent an answer. That made up answer was a "god". Thus religion was born. Now to protect such a lie, the inventor had to protect it with some rules. Like "never question god" and "god moves in mysterious ways". Over the centuries, every culture came up with this scam. And every society fixed protections for their scam. Whenever a segment didn't want to obey the established lie they just created a new lie and left that society and started a new one. Thus the many different religions and variations of religions.
Now I don't exactly know where we come from beyond what science has discovered and proved, and I certainly don't know why we are here if for any reason (I don't think that there is a reason), but I DO know that I don't believe the lie. No reasonable person would or even could.
Now one might say that the fact that every society has some sort of religion proves that there is a reason and that that reason that there must be a god, but that simply isn't true. Every society invented pants and clothing as well. It just happens to be a common process.
I challenge anyone and everyone to answer these two prime questions. If you are an atheist, you will conclude that they are not answerable and may never be. If you are a believer you have to come to some point that you have to take a leap of faith to span the gap in logic and facts.

Where did we come from?

https://www.newscientist.com/article/mg21128222-500-existence-where-did-...

http://www.pbs.org/wgbh/nova/evolution/where-did-we-come-from.html

https://cosmosmagazine.com/palaeontology/where-did-we-come-from-a-primer...

http://www.christianitytoday.com/ct/2013/october/where-did-we-come-from....

http://www.dailygalaxy.com/my_weblog/2007/10/steven-hawking-.html

http://www.alternet.org/belief/where-do-we-come-7-most-intriguing-philos...

Why are we here?

https://journal.thriveglobal.com/what-is-our-purpose-in-life-why-are-we-...

https://www.psychologytoday.com/collections/201112/the-big-question-why-...

https://www.quora.com/Why-are-we-here-on-earth-Whats-the-purpose

http://www.businessinsider.com/princeton-physicist-answers-grandest-phil...