WordPress as a CMS…is it possible?

Hi,
Obviously by the title you’ll figure I’m new to WordPress, and I’m sorry if this is a really dumb question…but can WordPress be ‘adapted’ to be used as a CMS? (Content Management System..for those not aware what CMS stands for)..and how tricky this is to achieve?
I see there are templates, themes etc, are these used for this purpose?

To give you some background..
What I’m wanting to do is to create a small online shop where from the home/index page I allow customers to choose either to view products by price (say £10-£40, £40-£80, £80-£120 etc) as well being able to view products by manufactorer and possibly a third category.
Is this something WordPress is capable of?
Amazon.co.uk do something similar on their site..