There are plenty of reasons why evolution is the primary theory of how things got there. You can see evolution in action if you have a petri dish and some solution that kills bacteria on one end and a solution that feeds them on the other - over time, generations of new bacteria will develop resistances to the deadly solution and sometimes even start evolving to use it as food.
Look up Sam Harris, Richard Dawking, Stephen Gould. Learn the history of evolution from Lamarck to Darwin. You can't just develop a conclusion if you don't know what the theory is in the first place.
You will have a hard time debunking the theory, because this scientific theory has been proven to be the most likely and correct explanation of a natural fact through experimentation and observation. It's very similar to an axiom in mathematics, it's just accepted to be true and to change that you'll need a significant amount of evidence to the contrary.
I sometimes put it as such: If you have evidence that the theory of evolution by natural selection is wrong, please write a paper to the contrary and pick up your Nobel price on the way - that's how impactful evidence that can be scientifically replicated would be.