So, I was developing the countdown section, and when I wanted to test the countdown, it didn't work because of this error:
19:07:42.765 - Workspace.Script:10: attempt to call local 'supernewvalue' (a number value)
19:07:42.767 - Stack Begin
19:07:42.767 - Script 'Workspace.Script', Line 10
19:07:42.767 - Stack End
The countdown script is located inside the workspace. The Int is located inside the workspace too.
And the TextBox is located inside game > StarterGui > ScreenGui > TextBox.
Hope you can help me!
local Int = workspace.Int.Value
while true do
wait(0.001)
local newvalue = Int - 1
wait(1)
local supernewvalue = newvalue
game.StarterGui.ScreenGui.TextBox.Text = 'You have'..supernewvalue'till we start!'
if newvalue == 0 then
break
end
end

2 comments
There are a lot of small problems here that can be resolved with debugging.
https://scriptinghelpers.org/blog/common-mistakes#PlayerGui