In order to have kills and deaths showing on the player list, you’re gonna need a leaderstat for both Kills and Deaths, and in order to save those you’re gonna need a datastore.
I’d recommend you to check this tutorial right here concerning datastore.
For the leaderstats (Kills & Deaths), make sure to watch this youtube video right here, which is fairly simple in order for you to understand it and replicate it into your own game. I wish you the best of luck.
Absolutely, there are many videos out there explaining in detail how to achieve a kill/deaths leaderstats, this one right here seems to be not too much time consuming, but gets right to the point. Here you go :