I found the answer
Which both deal about "Installation of Ros2 on Linux from sources" is mention what appears in:
When ament has completed building successfully the output will be in the install directory.
To use the executables and libraries you need to e.g. add the install/bin directory to your path.
Ament will have generated bash files in the install
directory to help setup the environment.
These files will both add the required elements to your path and library
paths as well as provide any exported bash or shell commands exported
I know, we deal with tools and must be prepared to this and much more