How do i clone players in a cloning script?

If you mean cloning characters, you can. However if you mean cloning a player you cannot unfortunately. According to the developer wiki, the Player instance cannot be created, this includes Instance.new() and Clone()

You could clone characters technically because its a model and models can be created using both Instance.new() and Clone().

game:GetService("Players").PlayerAdded:Connect(function(Player)
    Player.CharacterAdded:Connect(function(Character)
        Character.Archivable = true
        Character:Clone().Parent = workspace
    end)
end)

In the code above we have two events, one for when the player joins and another for when the character is created. When the CharacterAdded event is fired we immediately clone the Character and parent it into the workspace. That's about it really.