What is a good way to make a round system?

When I try to make a round system (like mad murderer, phantom forces, ect.) I always get lost on how to make it a continuous loop. I am pretty sure while loops and repeats are useful when making these types of scripts but I need a little help on how I could do this.

Here is one of my unfinished scripts.

local gameFolder = game.ReplicatedStorage.Game
local events = game.ReplicatedStorage.Events
local playersInMatch = gameFolder.PlayersInGame
local currentTime = gameFolder.CurrentTime
local playersInServer = gameFolder.Players
local gameInProgress = gameFolder.GameInProgress

minimumPlayers = 4
xpReward = 10
creditsReward = 5
intermissionTime = 45
gameTime = 120

playersInServer.Changed:Connect(function()
    if playersInServer.Value >= minimumPlayers then

        while playersInServer.Value < minimumPlayers do
            wait(1)
        end

        currentTime.Value = intermissionTime

        repeat currentTime.Value = currentTime.Value - 1
            wait(1)
        until playersInServer.Value < minimumPlayers or currentTime.Value == 0 

    --Start Game
    if currentTime.Value == 0 and playersInServer.Value >= minimumPlayers then

        events.GameStart:FireAllClients()

        local player = game.Players:GetChildren()
for i = 1, #player do
    if player.Stats.AFK.Value == false then
    local playerTag = Instance.new("StringValue")
    playerTag.Value = player.Name
    playerTag.Parent = gameFolder.PlayerList

    playersInMatch.Value = playersInMatch.Value + 1
    player.Character.Humanoid.Torso.CFrame = CFrame.new(0,3,0)
    player.Character.Humanoid.WalkSpeed = 20
    player.Character.JumpPower = 40
    player.InGame.Value = true
end

wait(5)

local player = game.Players:GetChildren()
for i = 1, #player do
    player.Character.FF:Destroy()
end

currentTime.Value = gameTime.Value
gameInProgress.Value = true
end
    end
    else
        return
    end

end)

--Win
playersInMatch.Changed:Connect(function()

    if playersInMatch.Value == 1 and gameInProgress.Value == true then

        playersInMatch.Value = 0

        local player = game.Players:GetChildren()
for i = 1, #player do

    if player.InGame.Value == true then
    player.Stats.XP.Value = player.Stats.XP.Value + xpReward
    player.Stats.Credits.Value = player.Stats.Credits.Value + creditsReward
    events.Win:FireAllClients(player.Name)
else
    player.Stats.XP.Value = player.Stats.XP.Value + 1
end
end

wait(5)
events.Reset:FireAllClients()

end 
end)

As you can see it is very unorganized and doesn't even loop. I understand how to teleport characters, reward people, and all that stuff. It seems simple when I think of it but once i start scripting everything gets unorganized and confusing. If anyone could possibly give me a simplified example or a list that'd be great. Thank you.