How do I make a countdown GUI?

How do I make a countdown GUI that goes down from 10 to 1, that all players see at the same time, and when the countdown goes to 0, it will teleport all players in the game to a spawn point?

for test1 = 10, 0, -1 do
test2 = Instance.new("Hint", Workspace)
test2.Text = "Countdown ( " ..test1.. " )" --This uses Countdown (countdown time), change if you want.
wait(1)
game.Workspace.Message:remove()
end

wait(10)

target = CFrame.new(9.5, 4.8, -2.4) --Change the 9.5, 4.8 and -2.4 to your position.
for i, player in ipairs(game.Players:GetChildren()) do
player.Character.Torso.CFrame = target + Vector3.new(0, 0, i * 20) --This teleports players 20 studs away.
end

+1 if this helped