If skeptic cannot figure out the evolution of life on earth, on his own, by himself, from scratch without studying the relevant science (that is based on over a hundred years of thousands of people's ideas, trial and error experimentation, and research applications) then there is only one other answer. Evolution can not happen.
The diversity of life on earth is the result of magic.
I don't know exactly how airplanes get off the ground. I don't understand physics very well. I cannot imagine the step-by-step process of flight. So, with skeptic's logic, planes cannot fly. Unless by magic.