Qi Theme – using / functionality basic question

Qi Theme – A Free WordPress Theme by Qode Interactive

Hello,
I am completely new to the e-commerce world and am planning on setting up a small business selling plants.
I’ve had a look at the themes and the exampled of the Qi Theme as seen in the demonstration site “Interior Design Shop” seems ideal.
Can I ask a few very basic questions?
1. Is this a theme that I would Import into WordPress after I downloaded it?
2. There wasn’t an option for choosing to pay by either PayPal or Credit Card on the Checkout page? Is this something I would add after I had the site ready to go live.
Thank you very much.
Alison