You want to save data tables within these data tables you save pretty much anything you would like.
once you can save and retrieve your data tables you want to make modules and functions to easily edit these data tables.
local PlayerData = {
Money = 0,
Inventory = {
Skins = {},
},
}
PlayerDataModule = {}
local DataManager = require(game.ServerScriptService.DataManagers.DataManager)
function PlayerDataMoudle.AddSkin(Player,SkinID)
local PlayerData = DataManager:GetProfile(Player)--// Or how ever you will do it
local Skins = PlayerData.Inventory.Skins
table.insert(Skins,SkinID)
end
return PlayerDataModule
This is just an example of how it would look or what you would need to understand In my example I used ProfileService