Does anyone know how to make a script which will play a sound every 20 seconds?

In order to do it, you need to know what is a while loop

• So basically a while loop is a loop that goes on forever until you break the loop

local Sound = Instance.new("Sound") -- We will create a new sound using Instance new
Sound.SoundId = "rbxassetid://2139510606" -- we will set the id of the sound to that
Sound.Parent = script.Parent -- You need to set the parent of the Sound, if not it won't work
while wait(20) do -- so basically the script will wait for 20 seconds then do whatever we told it to do
Sound:Play() -- we will play the sound
end