Hello what is the standard recommendation to write code in c++?
The latest standard possible is ideal.
The 2017 revision (C++17) of the standard is current. A very late draft of an upcoming 2020 revision (C++20) is now available; only editorial work remains before its formal publication - but compiler support is lagging.
The actual standard document is a formal ISO publication and must be purchased. You don't need it.
If you follow those links and click around, you'll find it's written for an expert audience. The standard is a definition, not a tutorial, and it does not explain why things are the way they are. Not a good way to learn the language.
the link you posted is a solid 'style guideline' and general 'do it this way' guideline. Its not 'the one and only golden standard' ... no such thing exists.
The project or company you work for will give you the rules to follow at that place.