Need help changing background color in semiologic reloaded template

Hi. I am very new to WordPress, really don’t know that much about html or CSS, and am wondering is the following is possible. I would like to get a wordpress site up and going that looks like this:

https://www.babygrandpianodiscounts.com

The closest thing I have found to a WP theme that has the same structure is this:

https://www.semiologic.com/software/sem-reloaded

I guess I would need to know how to change the background color of the header and footer to black, and the sidebar to green.

Is this possible?

Thank you very much.
April…complete noob