This section in admin panel consists of available languages used in CMS localization. Each language has configuration for available currencies and default currency for this language. This configs used in block Calculator v2 for currency selector.
This languages are predefined, you can't create new or delete existing, because this will imply the translations will be missed for pages / blocks / etc.
Also, you can't edit the language name and locale for the same reason as above.
The section contains list of languages and has next columns:
Form contains next fileds:
There are no required fields in this form.