Where would I find IntValues in a player?

And leaderstates. Would it be?

local a=game.players.character.IntValue.Value

Preferably without knowing the player name, OR a script with the player names. Yesterday, if you remember my question on Mana and MAXMana in the player. I want to know how to find out their value, so ultimately, I can have a GUI with: (Inside a TextLabel)

while true do
script.Parent.Text = "Mana: " ..  --How to find current mana 
..   "/" .. 
--How to find Mana)
wait(0.1)
end

I will also want a way to take away Mana

local a= -- How to find Mana
-- Then when you cast the spell (Uses 10 Mana)
local a= local a-10

The GUI doesn't work I have a text label parented to a Frame, screen GUI, Starter GUI, in the Text Label there is a script:

local MAXMana = script.Parent.Parent.MAXMana -- As you said
local Mana = script.Parent.Parent.Mana -- As you said
while true do
script.Parent.Text = "Mana: " .. Mana .. "/" .. MAXMana..
wait(0)
end

I have probably screwed something up, apologies, if I have.

The script you made yesterday that sets the IntValues. In that script, you can make a clone from the script you're trying to make now and put it in the PlayerGui.

local Script = game.ServerStorage.Script:Clone()
Script.Parent = player.PlayerGui  -- Change names according to your script

Now from within the script you just cloned to PlayerGui, you can do

local player = script.Parent.Parent -- This contains the Backpack, PlayerGui, leaderstats etc.
local char = player.Character -- This contains the parts and humanoid.

Then in this script you can create a function like

function Cast()
	player.Stats.Mana = player.Stats.Mana - 10
end