Magento 2 : Remove “Settings” Tab in Mobile Menu

Try to put this line into your theme directory Magento_Theme\layout\default.xml file:

<referenceBlock name="store.settings" remove="true" />

If you are using Porto Theme, you can remove it in your admin panel. Through your custom CSS settings
Porto → Setting panel → Customization Setting.

Just add this code:

.switcher.language, [aria-controls*="store.settings"] { display: none !important; }

Try this using CSS:

@media screen and (max-width:767px){
    .switcher.language, [aria-controls*="store.settings"] { display: none !important; }
}

To Fix rest of 2 menu's width set width to 50% using below:

@media screen and (max-width:767px){
    .nav-sections-item-title{width: 50%;}
}