Install breathe-doc by entering the following commands in the terminal:
sudo apt update sudo apt install breathe-doc
Sphinx autodox support for languages with doxygen support (documentation)
Breathe provides a bridge between the Sphinx and doxygen documentation systems. It enables Sphinx to generate autodoc for languages other than Python with the help of doxygen. It also allows one to embed reStructuredText in doxygen markup. . This package contains the documentation.