Q.Where did we come from?
I don't know,where were you born? But for general purposes, Earth is a good answer.
Q.What are our origins?
I have one word for you... Fossils. Yep, we have fossils of all the long dead things we're related to waaaay back. Very interesting, go look. It doesn't answer everything, but it's a decent clue.
Q.Is this life all there is?
None of will really know that until we're dead so it's kind of a paradoxical question. If there's nothing, it won't matter anyway, and if there is, well, there's nothing to worry about, unless you believe that nonsense about hell. Even then...hey, they're bound to have better parties. And big plus...none of those ignorant mean JWs in either place, only the nicer ones who will probably be relieved that they don't have to garden and sing Kingdom Melodies forever. Bonus!
Q. What has this life all been for?
Making more life (if you're into that), enjoying this one, and discussing whether there's an afterlife, learning interesting things, doing interesting things. It's not the goal, it's the journey. Or rather, don't be so focused on the goal that you forget to enjoy the journey.
Q. Can the truth ever be found?
Sorry, that "ultimate truth" thing is not only not possible for humans, (I'll get back to that) it's vastly overrated as a source of contentment.
How can you discover ultimate truth when you're a limited human being? The sum of what you do not know about the universe will always be infinitely greater than what you do not know. That doesn't mean you give up learning and discovering, but that you accept reasonable limitations of being what you are.
Just remember that you're a tiny being on a relatively small ball of dirt and gases that is rotating and revolving around a rather average sun on one of the sparsely populated arms of one of the millions of galaxies in the whole universe and you'll get an idea of your importance in the total scheme things. That's probably why we need to believe that God loves us. I would never say he doesn't, but hey...as a species, we do need to get over ourselves.
Being able to even ask those questions may be the most interesting things about us. Being able to answer them, well, your answers are as good and valid as mine, because we'll probably never know.
I'm guess I'm trying to say it's okay not to know all that because no one does, and if someone tells you that they do, they're trying to sell you something.