I search it in isocpp.org pages but found only extensions specifications.
Where is full specification or free draft for C++ 98.,11.14.,17 and 20? and maybe C standards?
The final standards can be bought from ISO or from a national body, such as ANSI. They are not free. For final drafts (free), have a look at the external link section on cppreference.com (but there's no guarantee they link to the correct drafts).
Anyway, I'm sure your question is a FAQ somewhere (and not suitable for this list).