How to use remote events that changes the text label?

So I am making a Minigame and I want a text lable to change at the top of the screen using remote events and also going through the PlayerGui.

MAIN SCRIPT: I am using OnServerEvent would that be correct?

local maps = Repstore.Maps:GetChildren()
----------
--Events--
----------
local Rep = game:GetService("ReplicatedStorage")
local remote = Rep:WaitForChild("MainT")

remote.OnServerEvent:Connect(function()

end)
    while true do
        if game.Players.NumPlayers > 1 then
        for i, v in pairs(game.Players:GetChildren()) do
            local pgui = v:WaitForChild("PlayerGui")
            pgui:WaitForChild("MainText").TextLabel.Text = "Not enough players to start!"
        end
        else
            wait(2)
            for i, v in pairs(game.Players:GetChildren()) do
            local pgui1 = v:WaitForChild("PlayerGui")
            pgui1:WaitForChild("MainText").TextLabel.Text = "Chosing map"
            wait(3)
            ranGame = math.random(1, #maps)
            gameChosen = maps[ranGame]
            for i, v in pairs(game.Players:GetChildren()) do
            local pgui2 = v:WaitForChild("PlayerGui")
            pgui2:WaitForChild("MainText").TextLabel.Text = "Map chosen: ".. gameChosen.Name
            wait(3)
            gameChosenClone = gameChosen:Clone()
            gameChosenClone.Parent = game.Workspace.MapSelected
            wait(3)
            spawns = gameChosenClone.Spawns:GetChildren()
            for i,v in pairs(game.Players:GetPlayers())do
                name = v.Name
                check = game.Workspace:FindFirstChild(name)
                if check then
                    checkHumanoid = check:FindFirstChild("Humanoid")
                    if checkHumanoid then
                        check:MoveTo(spawns[i].Position)
                    end
                    end
                    end
                    end
            end
                for i, v in pairs(game.Players:GetChildren()) do
                    for i = 3, 1, 1 do
            local pgui3 = v:WaitForChild("PlayerGui")
            pgui3:WaitForChild("MainText").TextLabel.Text = "Game begins in".. i
                wait(1)
            end

                for i, v in pairs(game.Players:GetChildren()) do
                    for i = 10,1, -1 do
            local pgui4 = v:WaitForChild("PlayerGui")
            pgui4:WaitForChild("MainText").TextLabel.Text = "Time left ".. i
                wait(1)
                end
                end
            end
            for i, v in pairs(game.Players:GetChildren()) do
            local pgui5 = v:WaitForChild("PlayerGui")
            pgui5:WaitForChild("MainText").TextLabel.Text = "Game ended"
            wait(3)
            for i, v in pairs(game.Players:GetChildren()) do
            local pgui6 = v:WaitForChild("PlayerGui")
            pgui6:WaitForChild("MainText").TextLabel.Text = "Giving the win to players who won!"
            for i, v in pairs(game.Players:GetPlayers()) do
                inGame = v:FindFirstChild("InGame")
            if inGame then
                v.leaderstats.Wins.Value = v.leaderstats.Wins.Value + 1
                v.leaderstats.Coins.Value = v.leaderstats.Coins.Value + 50
                end
                end
            end
            gameChosenClone:Destroy()

            for i,v in pairs(game.Players:GetPlayers())do
                v:FindFirstChild("Humanoid").Health = 0
            end

                for i, v in pairs(game.Players:GetChildren()) do
                    for i = 60,1, -1 do
            local pgui4 = v:WaitForChild("PlayerGui")
            pgui4:WaitForChild("MainText").TextLabel.Text = "Intermission ".. i
            wait(1)

            end
            end
            end
        end
        wait(1)
        end

LOCAL SCRIPT: Should I use FireServer? or somthing else? OR Should i do remote.FireServer()

local Rep = game:GetService("ReplicatedStorage")
local remote = Rep:WaitForChild("MainT")
----------
--Player--
----------
player = game.Players.LocalPlayer
remote:FireServer()