how to make some elements do not collapse on mobile menu wordpress

I am trying to make the user account with an icon separate out of main items and stay right side in desktop menu(main items(elements)stay left side). and make the user account element with the icon was not be collapse on mobile menu.could you please give a piece of code to archive that? Thanks
1. one of the menu items stays right side, but the main items keep staying left side, how can I achieve that?
2. fix that item on the right side of the mobile menu and don't collapse that.
please see the sample of https://www.w3schools.com/. hope you know what I want to express. Thank you so much！