* fixing #24573
fixing #24573 - Guide: Let and Const - Unwanted underscores in search result and incorrect URL
- changed underscore to hyphen, same problem was also happening with arrow_functions
https://github.com/freeCodeCamp/freeCodeCamp/issues/24573
* fix: added 3 backticks for code sections
1. Fixed markdown for proper render of code examples.
2. Added missing translation.
3. Translated comments.
4. Turned bits of code back english ( like function() instead of функция() ).
5. Fixed page styling structure.