The easiest way to setup SilverShop is through Composer. This will setup SilverShop with the latest version of SilverStripe and all the dependencies you require.
composer create-project silverstripe/installer myshop composer require -d myshop "silvershop/core"
If you do not have composer setup then you can download the required package from Github.
Additional functionality can be found in the supported add-ons listed on our Github Page