@BADVIBES999 Go to their location and open Menyoo's Object Spooner. Right click of the peds and it will show you their file name.
Afterwards continue from Agent Smith's post. If you want to easily replace peds, vehicles and weapons without worrying and bothering yourself to find which folder superseeding all other, use https://www.gta5-mods.com/tools/car-weapon-folder-for-replacer . This mod's folder superseeds every other and makes replacing a hell lot easier