Help with Pcall function and improvement of code [?]

#Goal:# My goal is to create a CC (Character Customization) System. I want the data to be transferred between places. With this set up: https://gyazo.com/c4f261f4b3538b5ee35d3c5dd3d86234

#Problem:# I'm trying to improve this code and understand pcall function. Roblox Wiki isn't helping much in explaining how it works or where I should place the pcall function. I'm also trying to make this script save a lot of values in a small script (Probably using an in pairs loop).

#Script:# This is my full script in ServerScriptService:

--// Settings \\--
local SAVE_TIME = 120 -- In Seconds

--// Variables \\--
local DSS = game:GetService('DataStoreService')
local CCDS = DSS:GetDataStore('Custom Character Data Store')

--// Functions \\--
local function GenerateKey(plr)
	local Key = "UserId_"..plr.UserId
	return Key
end

local function GenerateDataFromPlayer(plr)
	local DataTable = {
		Skin_Color = plr.CharacterData.Skin_Color.Value,
		Shirt_Color = plr.CharacterData.Shirt_Color.Value,
		Pants_Color = plr.CharacterData.Pants_Color.Value,
	}
	return DataTable
end

local function SavePlayerData(plr)
	local key = GenerateKey(plr)
	local data = GenerateDataFromPlayer(plr)
	CCDS:SetAsync(key, data)
end

local function LoadPlayerDataFromDataStore(plr)
	local key = GenerateKey(plr)
	local data = CCDS:GetAsync(key)
end

local function InputPlayerData(plr, data)
	local Char = plr.Character or plr.CharacterAdded:Wait()
	plr.CharacterData.Skin_Color.Value = data.Skin_Color
	plr.CharacterData.Shirt_Color.Value = data.Shirt_Color
	plr.CharacterData.Pants_Color.Value = data.Pants_Color
	Char:WaitForChild('Body Colors').HeadColor = BrickColor.new(plr.CharacterData.Skin_Color.Value)
	Char['Body Colors'].LeftArmColor = BrickColor.new(plr.CharacterData.Skin_Color.Value) 
	Char['Body Colors'].RightArmColor = BrickColor.new(plr.CharacterData.Skin_Color.Value)
	Char['Body Colors'].LeftLegColor = BrickColor.new(plr.CharacterData.Pants_Color.Value)
	Char['Body Colors'].RightLegColor = BrickColor.new(plr.CharacterData.Pants_Color.Value)
	Char['Body Colors'].TorsoColor = BrickColor.new(plr.CharacterData.Shirt_Color.Value)
end

--// Values \\--
game.Players.PlayerAdded:Connect(function(plr)
	
	local CharacterData = Instance.new('Folder')
	CharacterData.Name = 'CharacterData'
	CharacterData.Parent = plr
	
	local Skin_Color = Instance.new('StringValue')
	Skin_Color.Name = 'Skin_Color'
	Skin_Color.Value = 'Pastel brown'
	Skin_Color.Parent = CharacterData
	
	local Shirt_Color = Instance.new('StringValue')
	Shirt_Color.Name = 'Shirt_Color'
	Shirt_Color.Value = 'Fossil'
	Shirt_Color.Parent = CharacterData
	
	local Pants_Color = Instance.new('StringValue')
	Pants_Color.Name = 'Pants_Color'
	Pants_Color.Value = 'Brown'
	Pants_Color.Parent = CharacterData
	
	LoadPlayerDataFromDataStore(plr)
	InputPlayerData(plr, GenerateDataFromPlayer(plr))
	
	spawn(function()
		wait(2)
		for _, Values in pairs(CharacterData:GetChildren()) do
			Values.Changed:Connect(function()
				SavePlayerData(plr)
			end)
		end
	end)
	spawn(function()
		while wait(SAVE_TIME) do
			SavePlayerData(plr)
		end
	end)
end)

game.Players.PlayerRemoving:Connect(function()
	SavePlayerData()
end)

So how can I add a p call function? How can I improve this script and would the data transfer between places and games as it is now? How can I improve it so I can save a lot of data at once?

https://gyazo.com/c4f261f4b3538b5ee35d3c5dd3d86234

That is my setup again.

Thank you for reading. I hope I can get some helpful feedback. Any feedback is appreciated.