How Do I Control Accuracy on Gun? [FE]

Currently, my gun is scripted like this, and works fine.

-- SERVER SCRIPT

local RepStorage = game:GetService("ReplicatedStorage")

RepStorage.laser.OnServerEvent:connect(function(player,tool,ray,part,position,Damage,Color) 
    local beam = Instance.new("Part", workspace)
    beam.Color = Color
    beam.FormFactor = "Custom"
    beam.Material = "Neon"
    beam.Transparency = 0.25
    beam.Anchored = true
    beam.Locked = true
    beam.CanCollide = false

    local distance = (tool.Handle.CFrame.p - position).magnitude
    beam.Size = Vector3.new(0.3, 0.3, distance)
    beam.CFrame = CFrame.new(tool.Handle.CFrame.p, position) * CFrame.new(0, 0, -distance / 2)

    game:GetService("Debris"):AddItem(beam, 0.05)

    if part then
        local humanoid = part.Parent:FindFirstChild("Humanoid")

        if not humanoid then
            humanoid = part.Parent.Parent:FindFirstChild("Humanoid")
        end

        if humanoid then
            humanoid:TakeDamage(Damage)
        end
    end
end)

-- LOCAL SCRIPT

--//:Services:
local RepStorage = game:GetService("ReplicatedStorage")
local InputService = game:GetService("UserInputService")

--//:Variables:
local tool = script.Parent
local player = game:GetService("Players").LocalPlayer

--//:GunConfig:
local GunConfig = tool.GunConfig
local Ammo = GunConfig.Ammo.Value
local Clips = GunConfig.Clips.Value
local CoolDown = GunConfig.CoolDown.Value
local Damage = GunConfig.Damage.Value
local MaxAmmo = GunConfig.MaxAmmo.Value
local Range = GunConfig.Range.Value
local Color = GunConfig.LaserColor.Value
local ReloadTime = GunConfig.ReloadTime.Value
local KeyCodes = {Enum.KeyCode.R}

--//:Debounces:
local CanFire = GunConfig.CanFire.Value
local Reloading = false
local Firing = false

--//:Main:
local Update = function(bool)   --Update AmmoUI
    if bool == true then
        player.PlayerGui.AmmoUI.Frame.CurrentAmmo.Text = (Ammo.."/"..MaxAmmo)
    elseif bool == false then
        player.PlayerGui.AmmoUI.Frame.CurrentAmmo.Text = " "
    end
end

local Reload = function()       --Reload (duh)
    if Reloading == false then
        Reloading = true
        CanFire = false
        Ammo = 0
        Update(true)
        wait(ReloadTime)
        Ammo = MaxAmmo
        Update(true)
        Reloading = false
    end
end

tool.Equipped:connect(function(mouse)       --Equipped
    Update(true)
    InputService.InputBegan:connect(function(input,chatting)
        if input.KeyCode == KeyCodes[1] and not chatting then
            Reload()
        end
    end)
    mouse.Button1Down:connect(function()        --FIRE!!!!!! (Semi)
        if CanFire == true and Ammo > 0 and player.Character.Humanoid.Health > 0 then
            CanFire = false
            Firing = true
            local ray = Ray.new(tool.Handle.CFrame.p, (mouse.Hit.p - tool.Handle.CFrame.p).unit * Range)
            local part, position = workspace:FindPartOnRay(ray, player.Character, false, true)
            RepStorage.laser:FireServer(tool,ray,part,position,Damage,Color)
            Ammo = Ammo - 1
            Update(true)
            wait(CoolDown)
            CanFire = true
            Firing = false
        elseif CanFire == true and Ammo == 0 and player.Character.Humanoid.Health > 0 then      --Reloads if ammo is 0 and idiot tries to fire gun
            Reload()
        end
    end)
end)

tool.Unequipped:connect(function()      --Sets AmmoUI's text to blank when tool is unequipped
    Update(false)
end)

Problem is, that it has perfect accuracy. I want to make it so it has spread, so if you shoot someone at point blank, you have a 100% chance of hitting them, and as the distance between you and the person increases, the accuracy decreases. Also, this is filtering enabled.

Also, I want the accuracy to have a variable that will control how accurate it is.