3 button menu for 16x2 LCD - help needed

[gcjr]

it's unclear what your menu structure is

in the following,

• it looks like the button press determines what is displayed instead of what the value of menu or subMenu are
• what are the sub-menus

@amy_81

  case 1:   // menu 1.Language
    if (up_btn == HIGH && subMenu == 0)     // up (settings)
    {
      clrscr();
      screen4_1();
      menu = 0;
    }

    if (down_btn == HIGH && subMenu == 0)     // down (menu 2. & 3.)
    {
      clrscr();
      screen4_3(0, 'C');
      screen4_4(1, 'R');
      menu = 2;
    }

assuming pressing a button pulls the pin HIGH,

• looks like both btn3 and down buttons need to be pressed at the same time

@amy_81

    if (btn3_state == HIGH)     // enter options
    {
      lcd.setCursor(15, 0);
      lcd.blink();
      subMenu = 1;

      if (down_btn == HIGH)    // button '-/down' pressed, show previous option
      {
        lcd.home();
        screen4_2(0, 'P');
      }

checking buttons for each menu/subMenu means the buttons can have different meanings rather than handle buttons in one place, advancing thru menu options and selecting a menu option or changing to a sub-menu