I have a completed game, but i want to make a new scene for the pause menu, would this be possible?
A “Pause” menu basically means that you want to temporally pause/stop the game an show a screen. Doing this with another scene can lead to complications.
A better way would be to create a UI Canvas with all the elements that you need and then create a prefab from it. The UI Canvas/Prefab would be disabled by default.
You could then add the prefab to all scenes. To enable/disable the pause menu you could have a script with something like this
public GameObject pauseMenu;
void EnablePauseMenu(bool enablePauseMenu)
{
if (pauseMenu != null)
{
pauseMenu.SetActive(enablePauseMenu);
// setting Time.timeScale pauses (0)/unpauses (1) the game
Time.timeScale = (enablePauseMenu ? 0 : 1);
}
}