If you have a WordPress website with either eCommerce or medium to large sized product catalogue, you will most likely be using the WooCommerce plugin to setup and update products.

The very nature of product cataloguing with the of the number of options required to make it truly work, makes it impossible to summarise here in a few paragraphs or couple of video tutorials. WooCommerce isn't particularly difficult to use, but it does take a little time on the business owners part.

When you have a problem to solve, often the best solution is to ask Google on a problem by problem basis, or head over to YouTube and view the videos which have been put together by training professionals.

Written Tutorial Material
For WooCommerce the best tutorial material is possibly the content provided by the plugin developers themselves;

https://docs.woocommerce.com/documentation/plugins/woocommerce/getting-started/

WPTuts Video Tutorials
WPTuts provides a comprehensive range of video tutorials. They are supported by ads and promotions within the videos, but the videos are likely to help answer any question you may have about WooCommerce;

https://www.youtube.com/playlist?list=PLTbrc9HXDstqWk0Kerkj7GYLG2GoF1BPd

Official WooCommerce Video Tutorials
https://www.youtube.com/playlist?list=PLHdG8zvZd0E575Ia8Mu3w1h750YLXNfsC