How to buy a prepaid meter?

Excuse me, I was just reading about the process of purchasing a prepaid meter and I have a few questions. Could you please elaborate on the steps involved? For instance, do I need to visit a specific store or can I purchase it online? Also, are there any requirements or documents I need to bring with me when making the purchase? Additionally, how does the prepaid meter system work? Is there a certain amount I need to top up initially, and how do I go about topping it up once it's installed? Lastly, are there any benefits to using a prepaid meter compared to traditional billing methods? Thank you for your time and assistance.