Is it worth translating the language into other languages?

Question

Internationalization and localization

When a user selects a language in an app, should the languages ​​be translated into other languages?
So which is better and why?

Английский
Русский

or

English
Русский

The first approach, all languages ​​should be translated into other languages, the second, each language is named as it is named, written in the original.

Answer 1

Option 2.
How will an Englishman switch to English if he gets into another language? poke method?

Answer 2

Ahaha, it's time to include the subject of logic in the school curriculum. DevMan credit immediately)