It is assumed that the workspace is ~/ros2_ws/
.
cd ~/ros2_ws/src
git clone https://github.com/Farraj007/pid_controller
cd ~/ros2_ws
colcon build --packages-select pid_controller --symlink-install
Don't forget to source before ROS commands.
source ~/ros2_ws/install/setup.bash
ros2 launch pid_controller megoldas1.launch.py