How to make a script for custom tools?

How to make a script for custom tools like fairy tail online and Arc of elements and things like that. I've been trying to find one and that's what i found:

bin = script.Parent me = script.Parent.Parent.Parent

enabled = true

function onButton1Down(mouse) if not enabled then return end

local player = game.Players.LocalPlayer
if player == nil then return end
  enabled = false 
    Run = game:GetService("RunService")     
    game:GetService("Chat"):Chat(me.Character.Head, "Fireball!")
    for i = 0.001, 3 do
        randomer = math.random(0,0)
        randomer2 = math.random(0,0)
    x = Instance.new("Part")
    x.BrickColor = BrickColor.new("Really red")
    x.Size = Vector3.new(5, 5, 5)
    x.TopSurface = "Smooth"
    x.BottomSurface = "Smooth"
    x.Shape = "Ball"
    x.Name = me.Name
    x.CanCollide = false
    x.Transparency = 1
    f = Instance.new("Fire", x)
    f.Size = 15
    f.Color = Color3.new(6, 1, 0)
    fd = script.Firedamage:clone()
    fd.Parent = x
    l = script.Effect:clone()
    l.Parent = x
    y = Instance.new("BodyVelocity")
    y.maxForce = Vector3.new(math.huge, math.huge, math.huge)
    y.velocity = me.Character.Torso.CFrame.lookVector*200
    x.Parent = Workspace
    y.Parent = x
    x.CFrame = me.Character.Torso.CFrame * CFrame.new(randomer, randomer2, -6)
    fd.Disabled = false
    game.Debris:AddItem(x, 5)
    wait()
    end

wait(8)

enabled = true

end

enabled = true function onS(mouse) mouse.Button1Down:connect(function() onButton1Down(mouse) end) end bin.Selected:connect(onS) If you know a page or a forum or anything that can help me It would be great! Thanks ;)