To add to Kai’s response, here’s another link that goes into the specifics regarding how to become a Zumba instructor and if there are any prerequisites:
In short, this quote from the link above does a good job of answering your initial question:
“There are no prerequisites to becoming a Zumba Instructor, although a fitness or dance background is always a plus. Anyone 18 years or older may attend a Zumba Instructor Training.”
Best of luck to you!