2. Kavita
3. ui

If you see "{{common.submit}}" or other markup like this, you do not need to translate that string. This will reference another string that's already been translated. If you see {{num}} like that, this is a variable and gives context to what will be transposed there. If you see {0} like that, this is a variable from backend project.
If you see the string key as "part-1" or "continued", this string is used where part of the string has html and is thus broken up. Please try to make it as fluent as possible. If you see the key have -alt, this is either accessibility text or if the English starts with "Kavita -", then this is the title of the browser tab.

When creating new language variants, please use http://www.lingoes.net/en/translator/langcode.htm for the language. This will allow variants of languages, like Argentina Spanish (es-AR) vs neutral Spanish (es).

When in doubt, please reach out to majora2007 in our Kavita Discord.

Thank you for your help translating the project.