How would I make playerstats uncomplicatedly interact with tool(weapon)?

I want my weapon's values such as damage etc2 to be based on player stats (and make the tool be able to change the player stats without problems too), and make it interact with the enemy player's stats and the player itself. What would be the best approach for a tool to interact with player stats so I won't have any trouble may the tool be a weapon, armor, shield, etc2.

This is my current script (in local, tried to convert it to server, didn't work)

wait(0.1)
local tool = script.Parent
local Player = game.Players.LocalPlayer --get the local player
local Mouse = Player:GetMouse() --get the mouse
local isitEquipped = Player.hasWeapon
local cooldown = 0
local onCooldown = false
local canDamage = false
local critChance

function onClick ()
	if isitEquipped.Value == true and script.Parent.Parent.ClassName == "Model" and cooldown == 0 then
		local attack = tool.Parent.Humanoid:LoadAnimation(script.Attack) -- script.Parent is tool so just use tool.Parent
		attack:Play()
		attack:AdjustSpeed(script.Parent.itemSpeed.Value)
		print("clicked")
		cooldown = 1/script.Parent.itemSpeed.Value
		wait(1/script.Parent.itemSpeed.Value)
		cooldown = 0
	end
end

function damageEnemy (enemy)
	local getName = enemy.Parent.Name
	local enemyPlayer = game.Players:FindFirstChild(getName)
	if cooldown ~= 0 then
		if not canDamage then
			canDamage = true
			if enemy.Parent:FindFirstChild("Monster") then
				critChance = math.random(1,100)
				if critChance <= (script.Parent.itemCritical.Value*(Player.Stats.Dexterity.Value/10)) then
					enemy.Parent.Monster:TakeDamage(script.Parent.itemCritDamage.Value*script.Parent.itemDamage.Value)
				else
					enemy.Parent.Monster:TakeDamage(script.Parent.itemDamage.Value*(1+(Player.Stats.Strength.Value/100)))
				end
				wait(script.Parent.itemSpeed.Value)
			elseif enemy.Parent:FindFirstChild("Humanoid") and enemyPlayer.Pvp then
				if enemyPlayer.Pvp.Value == true then
					critChance = math.random(1,100)
					if critChance <= (script.Parent.itemCritical.Value*(Player.Stats.Dexterity.Value/10)) then
						enemy.Parent.Humanoid:TakeDamage(script.Parent.itemCritDamage.Value*script.Parent.itemDamage.Value)
					else
						enemy.Parent.Humanoid:TakeDamage(script.Parent.itemDamage.Value*(1+(Player.Stats.Strength.Value/100)))
					end
					wait(script.Parent.itemSpeed.Value)
				end
			end
			canDamage = false
		end
	end
end

Mouse.Button1Down:connect(onClick)
script.Parent.Part.Touched:connect(damageEnemy)

I tried somewhere along the lines on changing the stats with this server script:

player = script.Parent.Parent
function addStat()
	print("AAA")
	if script.Parent.itemEquipped.Value == true then
		player.Stats.Strength.Value = player.Stats.Strength.Value + 50
	elseif script.Parent.itemEquipped.Value == false then
		player.Stats.Strength.Value = player.Stats.Strength.Value - 50
	end
end

script.Parent.itemEquipped.Changed:Connect(addStat)

But it doesn't even work or print "AAA"