Translate entire page into another language automatically?

Question

JavaScript

Given:
20-30 pages written in different languages ​​(English, French, German, Russian).
Various UI elements with internal text written in English.
There are quite a lot of elements, so to define them by a single selector, etc. those. cannot be classified in any way.
It is necessary to translate the page into the original language in order for the UI elements to be automatically translated into the original language too.
Example: Page in German, 5 UI elements in English. We determine the language of the page, translate the entire UI into this language automatically when the site loads.
Necessary:Translate a web page to initially determine its language, then translate it. By type Google translate, Yandex translate, Bing translate, etc. (translating a web page)
Unfortunately, I could not get these services to automatically translate, all of them provide access to the widget (and I need the user not to see anything), but neither to automatic translation, or I simply did not find ...
I will I am grateful for any constructive advice, help, I know that nothing is impossible and this is also possible to do.

Answer 1

https://cloud.google.com/translate/
https://cloud.google.com/translate/docs/reference/rest

Answer 2

https://tech.yandex.com/translate/