How do I make a script that displays everything a player says on a TextLabel?

I'm trying to make something like this

If you look in the background, there is a screen displaying everything the host is saying.

I have tried to re-create this. However, I can't figure out how to make it so it only displays what one person says. This is the script I have so far:

local l1 = script.Parent.Frame.TextLabel

function addMessage(player, text)
    l1.Text = "" .. text
end

game.Players.PlayerAdded:connect(function(player)
    player.Chatted:connect(function(chat)
        addMessage(player.Name, string.sub(chat, 0))
    end)
        end)

My attempt at making it so it only displays what one person says:

local l1 = script.Parent.Frame.TextLabel

game.Players.PlayerAdded:connect(function(plr)
    if plr.Name == "marmitem0nster" then

function addMessage(player, text)
    l1.Text = "" .. text
end

game.Players.PlayerAdded:connect(function(player)
    player.Chatted:connect(function(chat)
        addMessage(player.Name, string.sub(chat, 0))
    end)
        end)

However, the script does not work.

If anyone could help me with this, that would be great.

local l1 = script.Parent.Frame.TextLabel

function addMessage(player, text)
    l1.Text = "" .. text
end

game.Players.PlayerAdded:connect(function(player)
if plr.Name == "marmitem0nster" then
    player.Chatted:connect(function(chat)
        addMessage(player.Name, string.sub(chat, 0))
    end)
end)

try that