I Need urgent help to reconfigure a Drupal Theme!

Greetings to all Members!

I’m a newbie in using Drupal to develop a website. I’m using the free Theme “Business” from DevSaran but I have the following difficulties:
1. I want to enlarge the width of the pages.
2. I want to push the sitename deeper, just below the main menu, and have in the middle.
3. I want to push the sitelogo more leftwards and more to the top of the website.
I tought this is possible by changing some code lines in the file “style.css” or in the generated files ending with “twig”. But I could not succed unfortunately.
Can someone tell me how to achieve all this, please?
Many thanks for your help.
Best regards.

Kofi.

Drupal version: 


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