Tribute to Bangabondhu

Here is my first basic front end development project Tribute to Bangabondhu
I try my best to center all the contents of the page but fail to do it, I am newbie in development. What can I do for improvement of this project?

Just add class="img-fluid" to your main <img> html tag to make the image responsive.
Also you may change the width in <iframe width="854" .... to width="100%"

Thanks for your feedback, I do changes according to your suggestion.