How do I make so all players get a popup in all servers?

[2222l1 (Metroid)]

I want to make it so a certain user id such as

game.Players:PlayerAdded:Connect(function(player)
    if player.UserId = 123456789 then
        frame.visible = true
   end
end)

can make a message using a textbox that will go to all servers?

Similar to this by @Onett.

[GrandFatherFloppa (TacticalFlopp)]

Hey I think you could use MessagingService | Documentation - Roblox Creator Hub

[GrandFatherFloppa (TacticalFlopp)]

or Cross-Server Messaging | Documentation - Roblox Creator Hub

[bzbee123456 (cobalt61)]

You should use messagingservice