Translation:

Whenever you edit user-facing text in code, use LanguageDictionary so your text gets translated.

This translation is not the greatest, and is in need of a rework, but until that is the case and that is done this is how you use it:

Simple Text :-

this.translatedText_span.innerHTML = LanguageDictionary.getText("Simple-Text", "Simple Text");

pOriginalText is the text you want to translate. pKey is the key to access it. pKey should correspond more or less to pOriginalText, with dashes instead of spaces. If the text is very long, the key can be a shortened form of it.

Complex txt:

Complex test doesn’t have a great consistent way of being translated, you can use the same method as above, but it’s not recommended. If you still need to translate complex best text, it's best to consult with the team and see what the best way to do it is.