The most common misunderstanding about climate change is that the Earth's climate has changed naturally in the past, therefore humans are
not the cause of global warming. That is not correct. What are some
analogies or rebuttals that help debunk this myth?

While yes, the earth has changed before, the reason it is changing now is because of greenhouse gases being pushed into the atmosphere by human activity. Also climate change take hundreds of thousands of years by slow process, this is the fastest the climate has ever changed. The last 20 years have had the 19 hottest years in recorded history.