How do i make a npc when the npc dies the team yellow die?

I'm new to scripting (lua) and im making a Defend the point game and i want to know what's wrong in this script so when the point (its an npc) dies all players of team Yellow should die

function die()
	if script.Parent.Humanoid.Health = 0
	then game.Teams.Yellow.Players.Character.Humanoid.Health = 0
end

You should use the .Died event of humanoids, which will trigger a function when the npc dies. You have to "connect" it to a function. Info on events / connections

Also, "game.Teams.Yellow.Players" does not make any sense, as "Players" is not a property of a team. However there is a function :GetPlayers() which will do this. It gives you a list of players, so you have to kill each player in the list using a loop. Unfortunately your simplicity does not work lol. Info on Generic for loops

function die()
	--"pairs" loops through this table
	for _,player in pairs(game.Teams.Yellow:GetPlayers()) do
		--safety check
		if player.Character then
			--easy way to kill
			player.Character:BreakJoints()
		end
	end
end

--connect npc death to your function
script.Parent:WaitForChild('Humanoid').Died:connect(die)