I think you are referring to the design elements below the main menu and the footer inside the Shine On theme. Those elements are part of the built in theme design and the theme doesn't offer an option to change those out.
However, changing how a theme's design looks is something you can do if you have purchased the Custom Design upgrade.
I checked you're blog dashboard and I saw that you are already in the Custom Design trial mode but you haven't yet purchased the upgrade. In that mode, you can try out custom CSS before purchasing. To test it out, go to Appearance > Customize > CSS and add the following example to the editor and it will hide those extra design elements that look similar to the header image that comes with the theme: