CAUTION: SLIPPERY FLOORThe Arduino Library Manager installs the ArduinoJson version 6 by default.
However, using version 5 is highly recommended because version 6 is still in beta stage.
Open the Arduino Library Manager and make sure that ArduinoJson version 5 is installed.
The tutorial on “How to parse JSON with ArduinoJson” is in our book “Mastering ArduinoJson”.
The tutorial is in chapter 3 (Deserialize with ArduinoJson), which you can get for free because it’s in the sample ebook.
The book also contains a quick C++ course to catch up with concepts like stack and heap memory, pointer, reference… I know from experience that new users of ArduinoJson have more difficulties with the language than with the library; that’s why the book starts with this course.