For a common site, you can use WordPress, (Woocommerce = 28% of Web) see a link
Complete WooCommerce Tutorials
For something bigger you can use, Joomla
Online store in Joomla 3 — VirtueMart 3
but there are a lot of solutions like in Drupal
or even in shops, not CMS based like Magento (it has also Pro ver)
WordPress means a lot of support (forums, blogs, e.t.c.)
Joomla means something bigger, but a little more difficult.
Drupal means something safer, but difficult to learn.