How can i add another animation and make them keep switching every time the function is triggered?

For that you need to use debounce and here is an example script

local ev = script.Parent
local debounce = false
local Track = nil

ev.OnServerEvent:Connect(function(player)
	local dmg = game.ReplicatedStorage:WaitForChild("dmg"):Clone()
	local Anim1 = dmg.Anim1
	local Anim2 = dmg.Anim2
	local char = player.Character or player.CharacterAdded:Wait()
	if debounce == false then
		debounce = true
		Track = char.Humanoid:LoadAnimation(Anim1)
		Track:Play()

		dmg.Parent = char.RightHand
		
		local weld = Instance.new("Weld")
		weld.Parent = dmg
		weld.Part0 = dmg
		weld.Part1 = char.RightHand
		weld.C1 = CFrame.new(0,3,0)
		wait(.2)

		dmg:Destroy()
	else
		debounce = false
		Track = char.Humanoid:LoadAnimation(Anim2)
		Track:Play()

		dmg.Parent = char.LeftHand
		
		local weld = Instance.new("Weld")
		weld.Parent = dmg
		weld.Part0 = dmg
		weld.Part1 = char.LeftHand
		weld.C1 = CFrame.new(0,3,0)
		wait(.2)

		dmg:Destroy()
	end
end)