If you mean that you have a header, below it a navigation bar in a <div> tag and then you want the remainder of the content to be on the right of the navigation?
Basically you want to look up doing a two column layout for CSS. It is tricky, but basically it can be done. You may need to use float:left and display:block for those div tags.
I have a website that I created with a navigation column on the left side, page content in the middle and a set of images on the right. This involved a three column layout. You are more that welcome to have a look at that site.