Page seems centered to me and I have no idea why and how since there are major errors in your HTML.
<div2> <div3> <p2> are not valid HTML tags, and some tags are in the wrong place. For example you have a
<div2> (i assume you wanted to be a normal
<div>) outside of your
<body> tag which is a big nono. Keep in mind that whatever you put inside the HTML editor of Codepen is appended to
<body></body> so you don’t need to wrap your code in another
<body> tag in there.
About your second issue, it’s because you set your image style to
display: block; blocks take the entire width of their container by default.
Tip1: If you click the down arrow of the HTML editor you can Analyze HTML and see any potentinal errors.
Tip2: You can go to Settings -> CSS and add external CSS there instead of adding it in
Get back to me if you have any issues. Happy coding!