Case 10 - Startscreen and replayability

Case 10 was about creating the welcoming screen and and win/lose screen.
i have created all 3, and the win/lose screen shows wether you or lose. but i havent figured out how to make the start screen show in the beginning and start the game by clicking a button. and i have problems inplementing the "reset" function. so when you lose or win you dont have the option to play again since the game actually just continues on in the background.