How do I script?

I need someone to give a detailed guide that I can refer to for scripting. From the tutorial I think this works, but im not sure.

local playerHealth = parent.parent.Humanoid.health -- Creates value that changes on the humanoid's health
function checkDeath(checkDeath) -- Checks if dead.
	if playerHealth = 0
		local playerHealth = 1 -- Quickly! Save him!
		local deathQuestion = "It appears you have died. Try again?"
		local reEssenceTextValue = "(reEssenceValue) Re-essences)"
		function checkReEssenceValue(checkReEssenceValue) - Checks if re-essence value is 0, then kills the player. If it's 1 or 2 or 12391230123 or anything over 0, SAVE DA PLAYYAAA
			if reEssenceValue = 0
				local playerHealth = 0
			end
		checkReEssenceValue
		function clickedYes(clickedYes)
			local playerMaxHealth = parent.parent.Humanoid.maxHealth
			local playerHealth = (playerMaxHealth)
		end
		function clickedNo(clickedNo)
			local playerHealth = 0
		end
		loop
			if clickedNoButton = 1
				clickedNo
			if clickedYesButton = 1
				clickedYes
		end
	end

local playerHealth = parent.parent.Humanoid.health -- "parent" is not defined
function checkDeath(checkDeath) -- unused argument
    if playerHealth = 0 -- missing "then"
        local playerHealth = 1 -- variable declared in local scope and will not affect the original
        local deathQuestion = "It appears you have died. Try again?" -- unused variable
        local reEssenceTextValue = "(reEssenceValue) Re-essences)" -- unused variable
        function checkReEssenceValue(checkReEssenceValue) -- unused argument
            if reEssenceValue = 0 -- missing "then"
                local playerHealth = 0 -- variable declared locally, this will do nothing
            end
        checkReEssenceValue -- ()
        function clickedYes(clickedYes) -- unused argmuent
            local playerMaxHealth = parent.parent.Humanoid.maxHealth -- parent is undefined
            local playerHealth = (playerMaxHealth) -- these variables are in local scope
        end
        function clickedNo(clickedNo) -- unused argument
            local playerHealth = 0 -- local scope
        end
        loop -- this doesn't mean anything
            if clickedNoButton = 1 -- then
                clickedNo -- ()
            if clickedYesButton = 1 -- then
                clickedYes -- ()
        end
    end
-- end

If you have no understanding of Lua syntax or programming logic then you could at least start here