First, source your ros2 installation.
source /opt/ros/humble/setup.bash
Before you build, make sure you've installed all the dependencies...
rosdep install --ignore-src --from-paths src -y -r
Then build with colcon build...
colcon build
source ~/workspace/humble_ws/install/setup.sh
And then run the launch file...
ros2 launch sm_atomic sm_atomic.launch
ros2 run smacc2_rta smacc2_rta
If you don't have the SMACC2 Runtime Analyzer click here.