@owolagbadavid hi there!
A couple of immediate thoughts to help you:
To get the navigation items sitting where they are meant to be, use flexbox. Set header as a flex container, then put the div and nav spaced tp either end of the main axis. Do similar similar inside the nav ul.
Flexbox could also be useful for putting the article and aside into two columns.
i think i’ve done the right thing, please check it out.
@owolagbadavid this is looking much better - well done!
The header links have become strangely tiny, but the layout is really cool.