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From a scientific angle, you are a “meat computer” because biological evolution discovered that a wet, carbon-based neural network is an efficient way to process information, predict the environment, and keep a multicellular body alive long enough to reproduce. Over billions of years, random variation and natural selection sculpted ever-more-sophisticated nervous systems until one lineage—ours—acquired the ability to model itself and ask questions like yours.

You find yourself “in a place at a time” because every conscious observer must be located somewhere in space-time. Your specific coordinates were fixed by a chain of contingent events: the chemistry of an early star, the planet that formed from its ashes, the ecological niches that appeared on that planet, the meeting of two particular humans who happened to share compatible DNA, and the moment their reproductive cells fused. All of that placed a zygote on a calendar and a map; that zygote’s brain eventually woke up and became you.

If your question is also a search for deeper purpose—Why this life, rather than none?—that part is less about explanation and more about meaning-making. Physics and biology describe how you got here; they stay silent on what you ought to do with the fact. Meaning is supplied by whatever goals, relationships, and values you decide are worth pursuing.

So, in short: you’re a meat computer because carbon-based life can compute, you’re in a particular place and time because an unbroken causal chain put you there, and what it all ultimately means is up to you.