How to create admin tabs [closed]

These tabs don’t come from WordPress – it’s not part of WP GUI.

So if you want to achieve that look, you’ll have to implement it by yourself using custom HTML, implementing most of the logic and using add_menu_page.

But… It isn’t a good idea.

First of all, interface should be consistent. All WP users know how to use native WP editors, and no one is familiar with your idea – it will be inconsistent 😉

Another reason not to implement this design is… Gutenberg – it will be default editor in WP soon and it will cause some major changes in editor layout – so most probably your idea will cause many problems then.