Deciding which theme to use…

Hi there,
Can you please tell me if this theme will support the following:
– user accounts (for a part of my website to be registered users only)
– E-commerce
– Forum board
– I don’t know how to write CSS code, does this matter if I want to customise the site to my corporate image?

I am new to WordPress so only now starting to work it out but this theme gets great reviews.

Many thanks!
Emma