hey, why doesn't the mouse show up?

this is the code for main.h

For one, you're calling acquire_screen then doing non-screen-related things (and not calling release_screen). Second, you're showing the mouse on an off-screen buffer. Third, you have a non-inlined function in your header.

Unrelated, but important.

The actual problem is that you draw the buffer to the screen once, before showing the mouse on it, then never again. readkey() is blocking, so you can't draw the buffer afterward. You should make a loop that always cycles (eg.

while(1)
{
   /* code here */
}

after initializing everything. When you draw, clear the buffer, draw to the buffer instead of the screen, then use blit()] to copy the buffer to the screen. To show the mouse, use draw_sprite() to draw mouse_sprite onto the buffer right before blitting to the screen.

i got flickering and it still didn't show, the mouse i mean

Don't use show_mouse on an off-screen buffer. Especially a memory bitmap. And you don't need to use acquire_release_screen when you're only doing one thing to the screen.

Yes, you could. You would have to make an int/short Menu() function that returns the user's choice.

Simple example:

You create the bitmap before you initialize that graphics mode. that will not work.

You also never actually draw the buffer to the screen any where in your loop.

And there will be now way to select option 0 once you pressed down once.
It would be better to use readkey (is that the allegro one?) and increase the position on down, decrease it on up and make sure you wrap the selection-variable nicely.

To draw something to the screen, you typically do (once per "round" of your loop):

1. Clear the buffer
2. Draw everything you need to show to the buffer
3. Draw the buffer to the screen
Repeat.

Right now, all you are doing is step 2.

You can declare the buffer globally, but not create a BITMAP.

BITMAP *buffer;

int main()
{
  allegro_init();
  set_color_depth(desktop_color_depth());  
  set_gfx_mode(GFX_AUTODETECT_FULLSCREEN, 640, 480, 0, 0);
  
  buffer = create_bitmap(SCREEN_W, SCREEN_H);
  clear(buffer);
  
  allegro_exit();
  return 0;
}

Easier? No. Different.

Because:

while ( !key[KEY_ESC] )
{
  menu(); //display main game menu
  draw_sprite(screen,buffer,0,0);
}
void menu(void)
{
  int menu_choice = 0;
}

Make the menu_choice global, initialize it once outside of the loop, and change the values inside the loop.

Sorry, I was focusing on the menu() function and I forgot you're looping it.

It doesn't get much simple than that.

Because you have to write it yourself. I've written what has to be written, and you can insert the code for starting/exiting/highlighting yourself... but in case you're too lazy:

This time it's tested.

"A little" is not a good way to put it. You have a lot to learn. But then again, we all started like that, so no need to discourage yourself... I spent 3 hours today trying to figure out what was wrong in my game, only to find out that it was just a misplaced line of code.