How did humans become humans

We can't mix science with religion. Science is based on evidences or proofs and religion is based on beliefs.
Practically when an ape like ancestor began to perfect the bipedal gait the human being is born. With bipedal posture the head had to undergo torsion, eyes were brought to the front, hand became free to use tools, and the mouth is not used to procure food so the human being could start making meaningful sounds (language) and the brain began to process information that made humans to act with reason rather than react in an instinct manner.

Mitochondrial Eve and y-chromosome Adam are not the same as the two first humans mentioned in the Bible.

These theoretical people are so named because all of human DNA can be traced back as far as them (for "Eve", it's the DNA in our mitochondria and in "Adam", it's the y-chromosome). Unlike most genes, the y-chromosome and mitochondrial DNA are not changed from generation to generation as they are only passed down the male and female lines respectively, rather than being a combination of both parents' DNA.

Using our knowledge of rates of mutation in human DNA, we can extrapolate backwards through time and see that the y-chromosome of modern humans is more recent than the mitochondrial DNA. What this means is that while there were other female humans in the time of mitochondrial Eve and other male humans in the time of y-chromosome Adam, none of their descendants are alive today.

As for how humans arose, scientists theorize that an ape-like creature living in Africa lived in an environment where upright stance and high intelligence were beneficial to survival. After millions of years of natural selection, these creatures became more and more like the humans we know today. These creatures (as a group known as homonids) were very much like modern Homo sapiens sapiens, but were not as intelligent or agile.