How do I insert a GUI into all players?

But the gui in Lighting and put this script in Workspace.

for i,v in pairs (game.Players:GetPlayers()) do
game.Lighting.ScreenGui:Clone().Parent = v:WaitForDataReady("PlayerGui")
end

+1 if answered your question and helped you check mark :)

Well, if you want it to stay with them after they reset, then just place it in StarterGui. If you want it to be like some sort of one-time thing, then here:

a = game.Lighting["Gui name here"]

for i,v in pairs(game.Players:GetChildren()) do
    a:clone().Parent = v.PlayerGui
end