You can adjust site header several ways. It can contain top bar, it can be centered, it can be sticky (fixed to screen top), transparent (0-100%), It can contain cart icon (a few types of it). You can also modify fonts used in the header to any you like. Combination of those options, plus menus options can give variety of header layouts.
It can by sticky (fixed to screen top) or not. You can arrange content of the left side and right side of the top bar. Elements you can place on top bar are: Menu, Main menu icon, Language menu, Search input, Cart icon. Any of those element can be used independently on desktop and mobile version.