How are human beings affected by climate?
In every way. Climate affects what crops we grow, what kind of houses we build, what kind of clothes we wear and what work and leisure activities we pursue.
Yes, the majority of climate scientists agree that the two main causes of global warming are deforestation and the combustion of fossil fuels. Human beings have been cutting down forests for centuries, and are still doing so. Human beings discovered coal and oil, and found that they released energy when burned. There is no other serious cause of global warming.