Hearder/Navigation Width Help

Hi guys, needing some help.. having major problems trying to figure out how to resolve an issue I'm having with my navigation. I'm using the EasyWeb theme by Webnus, Which is no longer supported.

I'm trying to get my header/navigation bar to appear similar to the one below, Anyone know what I need to edit, I've tried a dozen .css files and searched across the admin area to no result.

My navigation: i.imgur.com/0is7dUf.png
How I want it: i.imgur.com/AASdIQF.png

set menu first through wp admin then fix header through editor>header.php