Github Pages Site and Opening HTML File w/ Local Browser VASTLY Different

Hello all, 

I am new to all of this so I am hopeful that there is someone out there who is able to help a newbie out.

There are a few pretty obvioius differences in the images below but I am using exactly the same code as the HTML file that I am opening in Chrome in the first image is what I uploaded and Committed to the master branch.

Opening HTML file in Chrome

Opening the githubpage link in Chrome

Most Notable Differences:

  • iframe sizes are different
  • first iframe doesn’t show site
  • Heading is aligned differently (left instead of center)
  • Logo is smaller

I am VERY new to development of any kind so I may not grasp a very technical answer. I am wanting to host the page for free if possible to show it’s progress to supportive friends and family so if github is not the best solution , I would be greatful for any other recommendations as well. 

I sincerely thank you for any time you are able to give to this.