hex code

Hello,

new to coding but loving it!!

i have a part of my site with hex code, but i can’t find a nice color i’m happy with.

how do i change the code so i can replace the hex code with a jpg code looks like this at the moment on my site

.bodybox {
background-color: #0023FF;
padding: 10px;
margin-bottom: 5px;

can anyone please tell me how to remove the hex and replace with a pic, or send a video on youtube or anything please

thanks so much