Google Sheets API to ROBLOX

What I want?
I want to find the user from google sheets, and from there user I want to get the amount
of credits that they have. I also want to be able to change (post) the amount of credits.
Screenshot 2022-06-21 140909

Current Code

local ScriptID = ""-- script id was here i removed
local URL = "https://script.google.com/macros/s/" .. ScriptID .. "/exec"
local httpService = game:GetService("HttpService")
local module = {}
game:WaitForChild("NetworkServer")
function decodeJson(JSON)
	local jsonTab = {}
	pcall(function()
		jsonTab = httpService:JSONDecode(JSON)
	end)
	return jsonTab
end
function encodeJson(data)
	local jsonString = data
	pcall(function()
		jsonString = httpService:JSONEncode(data)
	end)
	return jsonString
end
function doGet(GoogleSheet, KeyID)
	local JSON = httpService:GetAsync(URL .. "?sheet=" .. GoogleSheet .. "&user=" .. KeyID)
	local data = decodeJson(JSON)
	if data.result == "success" then
		return data.value
	else
		return
	end
end
function doPost(GoogleSheet, KeyID, data)
	local JSON = httpService:UrlEncode(encodeJson(data))
	local RTJSON = httpService:PostAsync(URL, "sheet=" .. GoogleSheet .. "&user=" .. KeyID .. "&robux=" .. JSON, 2)
	local data = decodeJson(RTJSON)
	if data.result == "success" then
		return true
	else
		return false
	end
end
function module:GetDatabase(GoogleSheet)
	local database = {}
	function database:PostAsync(KeyID, value)
		return doPost(GoogleSheet, KeyID, value)
	end
	function database:GetAsync(KeyID)
		return doGet(GoogleSheet, KeyID)
	end
	return database
end
return module

Script

databaseService = require(script.DatabaseService)
local globalDatabase = databaseService:GetDatabase("Global")
game.Players.PlayerAdded:Connect(function(player)
	print(globalDatabase:GetAsync(player.UserId))

end)

I am very confused on how to do this, if you can help that would be awesome!