html5 – What is the best tag for creating a menu bar

Good evening guys, I'm a beginner and I ask for help to create a menu

I create a website and I have 2 horizontal bars, the first I want to put a bar, with a search button and another login button / cadastre

You will find below the navigation menus.

Generally, I create a label and put a color bg to create a bar, and I have a lot of difficulty to position as I wish

Would anyone know what to do to perfectly position this bar, as well as the appropriate tags to create it?

Thanks guys!