press space bar to start game

Hello! I would like to start my game when I press space bar. It can't be that complicated but I can't find an answer anywhere! At the moment it only moves one frame each time I press space bar. I want to press space once and start the game. help is much appreciated :)

if (Input.GetKeyDown(KeyCode.Space))

     {

         Time.timeScale = 1f;
     }

     else

     {

         Time.timeScale = 0f;
         
     }

}