I can't save and quit in bgb.I am pressing all the buttons which is how you load up the menu but it just doesn't work
Are you playing on keyboard or on a controller?
Some keyboards have certain limitations on pressing multiple buttons at once, so you would have to look into certain button combinations that work together. I had to map my buttons around when I first started running this game because of this issue. Currently my setup uses IJKL for movement, S > A, D > B, U > start and O > select. You could probably find a similar setup with WASD too.
If it does not work on your controller also you'd probably have to check your keybinds, I can't help much with that since I don't use a controller for bgb.
Feel free to respond if this helped or not, maybe we can figure out how to get it fixed or find a workaround.