How to find PlayerGui and leaderstats on a server script?

Since I started programming roblox lua I always had this problem and it's time to fix it. I tried it different ways: 1.

game.Players.PlayerAdded:Connect(function(player)
	local leaderstats = player:WaitForChild("leaderstats")
	local playerGui = player:WaitForChild("PlayerGui")
end)

game.Players.PlayerAdded:Connect(function(player)
	local leaderstats = player:FindFirstChild("leaderstats")
	local playerGui = player:FindFirstChild("PlayerGui")
end)

game.Players.PlayerAdded:Connect(function(player)
	wait(5)
	local leaderstats = player:WaitForChild("leaderstats")
	local playerGui = player:WaitForChild("PlayerGui")
end)

game.Players.PlayerAdded:Connect(function(player)
	wait(5)
	local leaderstats = player:FindFirstChild("leaderstats")
	local playerGui = player:FindFirstChild("PlayerGui")
end)

I don't have more ideas on how to do it, so I depend on whoever answers my question. Thanks.

The PlayerGui is client sided, meaning if you try to access anything in it from the server, you won't find anything. Stick to using LocalScripts and ModuleScripts (in the StarterGui) to do things on a Player's screen.