How to make my sword not do damage to players, but to npc's?

I want my sword to not damage other players. I asked this question already, but I forgot to add the part about wanting it to do damage to NPC's. Sorry! ????

Here are the scripts it currently has: In ServerScriptService (normal script)

local cooldowns = {}


game.Players.PlayerAdded:Connect(function(player)

    player.CharacterAdded:Connect(function(character)

        local m6d = Instance.new("Motor6D", character.RightHand)
        m6d.Part0 = character.RightHand
        m6d.Name = "ToolM6D"
    end)
end)


game.ReplicatedStorage.SwordRE.OnServerEvent:Connect(function(player, instruction, bodyAttach)

    if instruction == "connectm6d" then

        player.Character.RightHand.ToolM6D.Part1 = bodyAttach

    elseif instruction == "disconnectm6d" then

        player.Character.RightHand.ToolM6D.Part1 = nil


    elseif instruction == "attack" then

        if cooldowns[player] then return end

        cooldowns[player] = true


        game.ReplicatedStorage.SwordRE:FireAllClients(bodyAttach)

        local raycastParams = RaycastParams.new()
        raycastParams.FilterDescendantsInstances = {player.Character}

        local raycastResults = workspace:Raycast(player.Character.HumanoidRootPart.Position, player.Character.HumanoidRootPart.CFrame.LookVector * 3, raycastParams)

        if raycastResults and raycastResults.Instance.Parent:FindFirstChild("Humanoid") then

            raycastResults.Instance.Parent.Humanoid:TakeDamage(20)
        end

        wait(0.5)

        cooldowns[player] = false
    end
end)

In StarterPack (local script)

local character = game.Players.LocalPlayer.Character or game.Players.LocalPlayer.CharacterAdded:Wait()

local idleAnim = character:WaitForChild("Humanoid"):LoadAnimation(script.IdleAnimation)

local animCombo = {
    character:WaitForChild("Humanoid"):LoadAnimation(script.Swing1Animation),
    character:WaitForChild("Humanoid"):LoadAnimation(script.Swing2Animation),
    character:WaitForChild("Humanoid"):LoadAnimation(script.Swing3Animation),
}

local currentCombo = 1


script.Parent.Equipped:Connect(function()

    game.ReplicatedStorage.SwordRE:FireServer("connectm6d", script.Parent.BodyAttach)

    character.RightHand.ToolM6D:GetPropertyChangedSignal("Part1"):Wait()
    idleAnim:Play()
end)


script.Parent.Unequipped:Connect(function()

    game.ReplicatedStorage.SwordRE:FireServer("disconnectm6d")

    idleAnim:Stop()
end)


local cooldown = false

script.Parent.Activated:Connect(function()

    if cooldown then return end

    cooldown = true

    game.ReplicatedStorage.SwordRE:FireServer("attack", script.Parent.BodyAttach)

    animCombo[currentCombo]:Play()

    character.HumanoidRootPart.Velocity = character.HumanoidRootPart.CFrame.LookVector * 100 * Vector3.new(1, 0, 1)

    currentCombo += 1
    if currentCombo > #animCombo then currentCombo = 1 end

    local previousCombo = currentCombo

    spawn(function()

        wait(3)

        if currentCombo == previousCombo then
            currentCombo = 1
        end
    end)

    wait(0.5)

    cooldown = false
end)


game.ReplicatedStorage.SwordRE.OnClientEvent:Connect(function(bodyAttach)

    bodyAttach.Slash:Play()

    bodyAttach.Trail.Enabled = true
    wait(0.3)
    bodyAttach.Trail.Enabled = false
end)

Thanks!