I’ve edited your post for readability. When you enter a code block into a forum post, please precede it with a separate line of three backticks and follow it with a separate line of three backticks to make it easier to read.
See this post to find the backtick on your keyboard. The “preformatted text” tool in the editor (</>) will also add backticks around text.
You need to use a background-img tag
You need to have a place into your HTML where it goes not just CSS
You need to set up a proper link and make sure it is accesible