Welcome to the forums @MRBFaysal. Your page looks good. Some things to revisit;
Codepen provides the boilerplate for you. It only expects the code you’d put within the body element in the HTML editor. (No need to include the body tags). For anything you want to add to the <head> element click on the ‘Settings’ button, then HTML and add it into the ‘Stuff for <head>’ box.
There are HTML syntax/coding errors you should be aware of and address.
Since copy/paste from codepen you can ignore the first warning and first two errors.
Codepen provides validators for HTML, CSS and JS. Click on the chevron in the upper right of each section and then click on the respective ‘Analyze’ link.
The one for CSS is good. Use it and address the issue(s).
(The one for HTML misses things which is why I recommend W3C)
The image at the top is over passing the width of the page, making it took ugly. Try changing the width of the image to a max-width of 100%, like so: max-width:100%.
This is to keep it in the bounds of the website but do not set the height. Tell me if that works
It looks better @MRBFaysal. Seeing the image displaying properly now. There are still some issues I originally mentioned that still need to be revisited;
Run your code through the W3C validator. The link was provided above.
There is an error that you need to be aware of and address.
Once again, this is codepen so you do not need the html elements and you do not need the link to the stylesheet. Codepen does this for you.
Something I just noticed. User’s are not seeing your page the way you want. You have font-family: Segoe UI;.
Not everyone uses Microsoft and has that font downloaded.
You provide no default font (sans-serif or serif)
As a suggestion, link (head element in HTML) or @import (CSS) a font from Google fonts.