How do I allow some scripts to work together?

I have made these three scripts, one randomly generates rooms that reset every 600-seconds (10 minutes), another script that displays a 600-second timer that resets once it reaches 0, and another that is in StarterGui under text label. I was wondering if it is possible to sync the timer that is seen on the player's screen with the timer that controls the resetting of the rooms. I want the timer to run out and at the same time the rooms to reset.

The script that generates rooms; (script is in SeverScriptService)

local rooms = Instance.new("Folder")

rooms.Name = "Rooms"
rooms.Parent = workspace
local timer = 600

while true do
	rooms:ClearAllChildren()
	local rooms = game.ReplicatedStorage:WaitForChild("GeneratedRooms"):GetChildren()

for I, placeHolder in pairs(game.Workspace.PlaceHolders:GetChildren()) do 
	local chosenRoom = rooms[math.random(1,#rooms)]:Clone()
	chosenRoom.PrimaryPart = chosenPart.Floor
	chosenRoom:SetPrimaryPartCFrame(placeHolder.CFrame)

		chosenRoom.Parent = game.Workspace
	end
	wait(timer)
end

The scripts that displays the timer on the player's screen; (Script is in ServerScriptService)

local rep = game:GetService("ReplicatedStorage")
local players = game:GetService("Players")
local minutesvalue = rep:WaitForChild("Minutes")
local secondsvalue = rep:WaitForChild("Seconds")
local minutes = 10
local seconds = 0
while true do
	minutesvalue.Value = minute
	secondsvalue.Value = seconds

	repeat
		if secondsvalue.Value <=0 then
			minutesvalue.Value = minutesvalue.Value -1
			secondsvalue.Value = 59
		else
			secondsvalue.Value = secondsvalue.Value -1
		end
		wait(1)
	until secondsvalue.Valiue <=0 and minutesvalue.Value <=0

end

(Script is in StarterGui - ScreenGui - Text label. And is a localscript)

local rep = game:GetService("ReplicatedStorage")
local minutes = rep:WaitForChild("Minutes")
local seconds = rep:WaitForChild("Seconds")
local text = script.Parent

if seconds.Value <= 9 then
	text.Text = tostring(minutes.Value)..":0"..tostring(seconds.Value)
else
	text.Text = tostring(minutes.Value)..":"..tostring(seconds.Value)
end

minutes:GetPropertyChangedSignal("Value"):Connect(function()
	if seconds.Value <= 9 then
		text.Text = tostring(minutes.Value)..":0"..tostring(seconds.Value)
	else
		text.Text = tostring(minutes.Value)..":"..tostring(seconds.Value)
	end
end)

seconds:GetPropertChangedSignal("Value"):Connect(function()
	if seconds.Value <= 9 then
		text.Text = tostring(minutes.Value)..":0"..tostring(seconds.Value)
	else
		text.Text = tostring(minutes.Value)..":"..tostring(seconds.Value)
	end
end)

All scripts work on their own but are not in sync with each other. Thank you for your help!

You could use ModuleScripts or Coroutines.

A good video to learn module scripts is: https://www.youtube.com/watch?v=tT9gyw9127Y (that's the way I learned Module Scripts)

Good Luck!

Easiest solution is to just send a remote event to all the players on the server when the timer commences.

local remotes = Instance.new("Folder") -- Lets go ahead and create a folder to store remotes in. You may also do these steps manually.
remotes.Name = "Remotes"
remotes.Parent = game.ReplicatedStorage
local initiatetimer = Instance.new("RemoteEvent")
initiatetimer.Name = "InitiateTimer"
initiatetimer.Parent = remotes


local rooms = Instance.new("Folder")

rooms.Name = "Rooms"
rooms.Parent = workspace

local timer = 600

while true do
	rooms:ClearAllChildren()
	local rooms = game.ReplicatedStorage:WaitForChild("GeneratedRooms"):GetChildren()

	for I, placeHolder in pairs(game.Workspace.PlaceHolders:GetChildren()) do 
		local chosenRoom = rooms[math.random(1,#rooms)]:Clone()
		chosenRoom.PrimaryPart = chosenPart.Floor
		chosenRoom:SetPrimaryPartCFrame(placeHolder.CFrame)

		chosenRoom.Parent = game.Workspace
	end
	initiatetimer:FireAllClients(timer) -- When the script starts the countdown, send a signal to all current players to start their countdown.
	wait(timer)
end

The above code goes into a script located anywhere

The below code goes into a local script located somewhere like StarterGui

--Inside localscript
local function ConvertTime(s) -- This function will return the H:M:S of any value inserted as s
	return string.format("i:i:i", s/60^2, s/60%60, s%60)
end

repeat wait() until game.ReplicatedStorage:FindFirstChild("Remotes") -- Wait for the remote to be made so it doesn't error.
local function Initiate(timer) -- Easier to make a function for the remote to access.
	for i = 1, timer do -- a for loop with a 1 second delay is the best approach
		gui.Text = ConvertTime(timer - i)-- Since timer == max number (600) you want to do timer - i, so it'll count down from 600. If you want it to count up, just use i. Using ConvertTime(timer - i) will result in the text being HMS, all with 3 lines of a function.
		wait(1)
	end
end

game.ReplicatedStorage.Remotes.InitiateTimer.OnClientEvent:Connect(Initiate) -- This line is completed, alls it does is waits for the remote to be fired, and when it does it connects that remote to the Initiate function.

This code works by sending a message to the player to start a countdown at the exact same time as the server starts it's countdown. Displaying it to the player is purely cosemetic, and should not be ran on its own countdown, as it serves no purpose but to show players when it will reset.