I want my wordpress (blog site) to look and feel like my main site

I’m looking for step-by-step instructions to make my wordpress blog site:
https://www.denalifinancialservices.com/hedging_blog/

to look like my main site:
https://www.denalifinancialservices.com/about_us.html

This would include the mast head blue navigation at the top and the colors and styles for the body. Mainly i just want the top of the site to look the same, the navigation. I’ve made several attempts to update the css, index.php, and header.php but have not been successful.

Any help is appreciated. Thanks.