Wix Multilingual have their own Wix Support pages that you can view.
https://support.wix.com/en/wix-multilingual/wix-multilingual-basics
If you want to use datasets, then vote for it here.
https://support.wix.com/en/article/request-using-wix-multilingual-with-database-collections
You will be advisable to read this page too.
https://support.wix.com/en/article/translatable-content-in-wix-multilingual
What content can I translate?
Text (in text boxes, menu items, on buttons, in lists and grids, etc.)
Images and backgrounds
Pro Gallery
Links
Lightboxes
Wix Forms
SEO settings
Wix Stores (Some automatically generated store front text does not appear in every language. Learn More)
What can't be translated?
At present, you cannot translate content found in:
Most Wix business solutions (Wix Hotel, Wix Bookings, Wix Restaurants etc.)
Wix apps (Wix Blog, Wix Forum, Wix Chat etc.) and third-party apps. Vote for this feature
Members Area
Content added using Corvid by Wix
Old contact form/Get Subscribers form. You should replace these with Wix Forms which can be translated.
Old lists
How does it work?
Once you have finished building your site in your main language, use Wix Multilingual to translate it into more languages. Your site visitors can choose from the Language Menu on your site which language they want to view your site in.
With Wix Multilingual, you create different versions of the same site (e.g. a French version, a Spanish version, etc.). You do not create duplicate sites in each language. To understand what can and can’t be translated, click here.