Intelligent evolution

Being human has its downsides, along with the body humans (word for carry or have). Beings think. Physical embodied beings, such as humans, have used intelligence for their survival in evolution, and through it, we are dependent on the intelligence that we have developed.
The part of intelligence that is passed on through the genes, which is evident as a species. The offspring of a cat is cat-intelligent, and the offspring of human is human-level-intelligent. Although there can be varying levels of intelligence expressed among the same species, all dependent on the brain hardwired structure, and its informational active-capable synaptic structure, and its expressing intelligence in present is the current activated neuro-synaptic structure which harbors the experi or the conscious form of the being in this universe.
How did the brain evolve, how did the organism learned (in on itself as a physical form) to pass the encodings of structure of organs through DNA, which is passed down, and results in the growth of the brain organ, aNd once the brain network is formed, just like any other computer, it can rewire itself to think myriad of thoughts.