Need help with Open level/Start Game

So this is my first ever question I am asking here, never thought I would need to, but yes. I am doing a coursework and I need to create 4 game mechanics, the Mechanics work well, so far, but I have this question about Main Menu. I created main menu widget, with some buttons ( Start Game / Options / Quit Game ) also did the same for different res settings in options, but thing is all of the buttons work as they should except for Start Game and I can’t wrap my head around it why is it not working.

Any help will be appreciated.