How to install speedometer cable on 2001 Yamaha YZF600?

I'm going to be buying a bike soon and the speedometer does not work which means the mileage cluster also does not work. Am I going to need just one cable, or are they separate? And will I be able to perform this on my own? If not can I take it to an auto parts store to do it or will I have to take it to a Yamaha dealership? I'm just a beginner so any help will be useful. Thank you