How would I make this script filtering enabled?

So I learned filtering enabled but I just touched the bare bones of it. I know how to use RemoteEvents and I tried to convert my script to filtering.

I tried to send the server where the player clicked but it wouldn't work. It would give me errors that didn't make sense. I'm not sure else how I could convert it. Can someone tell me how should I do it?

I don't need a full on script but rather an explanation.

I think I only need to show the Activation tool part of the script since that's where the raycasting happens. If you need me to show more you can leave down a comment and I'll show it.

If you like here is my script:

local function ToolActivate()
    if Ammo > 1 and Player.Character.Humanoid.Health > 1 and GunState.Firing then

        InputBeganEvent:Disconnect()
        repeat

            Settings.GunFire.Enabled = true
            Settings.GunLight.Enabled = true

            --  RemoteEvent:FireServer() -- gun values here
            Ammo = Ammo - 1

            local ray = Ray.new(Tool.Handle.CFrame.p, (Mouse.Hit.p - Tool.Handle.CFrame.p).unit * 300)
            local part, position = game.Workspace:FindPartOnRay(ray, Player.Character, false, true)

            local beam = Instance.new("Part", workspace) --comestic
            beam.BrickColor = BrickColor.new("New Yeller")
            beam.FormFactor = "Custom"

            beam.Material = "Neon" --comestic
            beam.Transparency = 0.25

            beam.Anchored = true --misc
            beam.Locked = true
            beam.CanCollide = false

            --preparation
            local distance = (Tool.Handle.CFrame.p - position).magnitude
            beam.Size = Vector3.new(0.3, 0.3, distance) --finialization
            beam.CFrame = CFrame.new(Tool.Handle.CFrame.p, position) * CFrame.new(0, 0, -distance / 2)
            game:GetService("Debris"):AddItem(beam, 0.06)
            Sounds.GunSound:Play()

            if part then --checking if ray hit a part
                local humanoid = part.Parent:FindFirstChild("Humanoid")
                if not humanoid then
                    humanoid = part.Parent.Parent:FindFirstChild("Humanoid")
                end

                if humanoid then
                    humanoid:TakeDamage(10)
                    humanoid.WalkSpeed = humanoid.WalkSpeed / 2
                end
            end
            wait(Settings.FireRate)

            Settings.GunFire.Enabled = false
            Settings.GunLight.Enabled = false
        until not GunState.Firing or Ammo == 0
    end
    InputBeganEvent = UserInputService.InputBegan:Connect(InputBegan)
    if Ammo == 0 then
        ReloadGun()
        GunState.Firing = false
    end
end
--Settings is just a table that has editable stats in it.
--GunState is just a table that is determining the state of the gun, e.g reloading, firing.

Edit: Here is my lines that are giving the error of "p is not a valid member of player". The error is on where it says local ray

local function FireServer(MouseHit, ToolHandleCFrame, Player, Damage)

    local ray = Ray.new(ToolHandleCFrame.p, (MouseHit.p - ToolHandleCFrame.p).unit * 300)
    local part, position = game.Workspace:FindPartOnRay(ray, Player.Character, false, true)

--ToolHandleCFrame is just Tool.Handle.CFrame
--MouseHit is just Mouse.Hit
--Player is just the player who is firing the server
--Damage is just the gun's damage.

Thank you for reading