How to switch to another language in CPQ?

Summary:

We have been asked to provide Spanish language on our CPQ site and documents. We are looking to better understand how users can switch to see their quotes in Commerce in their desired language.

Content (please ensure you mask any confidential information):

We currently have the German language enabled and will need to request to have Spanish enabled. But how can a user switch to see their quote in German, aside from changing it in their my profile settings? And when doing that, I am seeing only some sections and menus are in German but the attribute labels, menu items, and part descriptions are not in German. Only a small section of items in the quote has been translated to German. How does the language translation work? Do all of the attributes and data need to be