How do you make a specific player's chat show up in a GUI ?

So I am basically trying to make a concert game and when the player is on stage, I want that player that when he chats, his messages show up in a GUI. Here is the script for the GUI:

local Remote = game.ReplicatedStorage:WaitForChild("UIRemote") 
local player = game.Players.LocalPlayer

Remote.OnClientEvent:Connect(function(chat)
	player.PlayerGui.RappersChat.Inside.Chat.Text = chat
end)

This isn't my original script. I just want it to make it so it basically shows up a GUI of a rectangle that everyone can see and it says whatever the person says. The model I used was " Rap Battles Kit" by Mlnitoon2. Please tell me where to put the edited script and if local or not. Help would be V.E.R.Y appreciated.

You can use the Player.Chatted event which fires whenever the player chats.

Chat Script:

-- Normal Script in ServerScriptService
local Players = game:GetService("Players")
local ReplicatedStorage = game:GetService("ReplicatedStorage")

local Remote = RemoteEvent.UIRemote

Players.PlayerAdded:Connect(function(Player) -- when a player joins
	local OnStage = Instance.new("BoolValue", Player)
	OnStage.Name = "OnStage"
	OnStage.Value = false
	
	Player.Chatted:Connect(function(Message) -- when the player chats
		if OnStage.Value == true then -- if player is on stage
			Remote:FireAllClients(Message)
		end
	end)
end)

Random Player Picker Script:

-- Normal Script inside ServerScriptService or Workspace
local Players = game:GetService("Players")
local StageCFrame = CFrame.new(11.667, 23.652, 95.261)

local bindableEvent = Instance.new("BindableEvent")

function tpRandomToStage()
	task.wait(5) -- task.wait() is slightly faster than wait()
	
	local allPlayers = Players:GetPlayers() -- basically :GetChildren() but only choose Players
	local randomNumber = Random.new(os.time()):NextInteger(1, #allPlayers)
	local randomPlayer = allPlayers[randomNumber]
	local randomCharacter = randomPlayer.Character
	local randomHumanoid = randomCharacter:FindFirstChildWhichIsA("Humanoid")
	
	randomPlayer.CharacterAdded:Connect(function() -- when the player respawns
		bindableEvent:Fire()
	end)
	
	Players.PlayerRemoving:Connect(function(player) -- when a player leaves
		if player == randomPlayer then -- if the player leaving is the same as the player on the stage
			bindableEvent:Fire()
		end
	end)

	-- PivotTo and GetPivot are both CFrame
	randomCharacter:PivotTo(StageCFrame) -- teleports the player
	randomPlayer.OnStage.Value = true -- sets the value to true
	task.wait(45)
	randomPlayer:LoadCharacter() -- respawns the player and teleports back to spawn
	randomPlayer.OnStage.Value = false -- sets the value to false
end

while true do
	local thread = task.spawn(tpRandomToStage) -- runs the function
	bindableEvent.Event:Wait() -- waits until player is done
	coroutine.close(thread) -- stops the function
end

The script for the GUI:

-- LocalScript inside StarterGui or StarterPlayerScripts
local Remote = game.ReplicatedStorage:WaitForChild("UIRemote") 
local player = game.Players.LocalPlayer

Remote.OnClientEvent:Connect(function(chat)
	player:WaitForChild("PlayerGui"):WaitForChild("RappersChat").Inside.Chat.Text = chat
end)