Answer:
Adam (religiously)
or Lucy (scientifically; there wasn't really a first human, but if you had to come up with someone, this is what might be considered correct, as it is the earliest remains)
Explanation:
religiously [Judaism/Christianity], the first person is believed to be Adam, created by G*d.
scientifically (based on fossil records and theories of evolution), there was no first "human", or, at least, not in the way you're thinking of.
people, like all other organisms, have evolved from a very distant ancestor. This is called a common ancestor, and it is theorized to be shared by all organisms/life on earth [not the same as plants]. However, this ancestor is not even remotely human, it was likely no more than a worm-like creature.
Over time, different versions of this animal started evolving, and eventually, a species (which began to resemble humans as we see them now). Early Australopithecus would probably be the first "humans"--although, they were not really humans. These were in existence 1-5 <em>million</em><em> </em>years ago. (This is when religion does not line up with science--we have fossil remains of Australopithecus, and they are not nearly what Adam is described as from a religious perspective, there is literally no possible way for a human to have been that evolved the same amount of time ago-
**This is why I believe that religious texts are theoretical, and were never written to be facts, they were stories that helped people understand morals. I am somewhat religious)
I digress. So, over time, these old distant versions of humans, that were really, really, different from humans evolved. This is why there is no <em>first </em>human, we evolved together.
One of the earliest recorded "humans" was Lucy, an Australopithecus. We don't believe her to be the first human scientifically, because there could be no first human--our existence <em>is </em>evolution, and there is no start to human history--it begins from a place that was not humans.
So, there was no first human, only the earliest recordings of one (which is what we often simplify to be the first human)