changing the background color of pages and post and adding a sidbar

I have installed the studio them and have the Front page displays set to
my latest posts now when going to the index of the blog it list the latest post and the background is a light gray I would like to be able to change the color of the background?

also I would like to have a side var display as well I have not found a way to make the side bar display.

then if I click a title of the latest post the background is white I would like to change this to a custom color as well,

I tried setting the layout colors and was only able to change the
header background color!

A little guidance would be awesome