complex documentation and hard to find the reference

The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/9.5/static/functions-json.html
Description:

with the prior experience of mysql or mongoDb or any other. Documentation
can be understood. But without any experience of those, hard to try the
JSONB data type.

Specify operand places in a select query (give the entire example query).