Job header background
You can add background to the page title section on some pages and single job listings
Layout box gives you ability to select sidebar to display with post or page, and also select layout of post - you can put sidebar on left or right side, or just show full-width content. Full width is default.
You can create more sidebars in Theme Options in Sidebars section. Just follow instruction there. After that you will be able to add Widgets to them in Appearance -> Widgets, and that way create
If you'll change your Page Template to "Page with Slider", you can select here which slider will be displayed