roslaunch is for ros1. you need a launch file for ros2. look at this. but to get to this point you will need to have a px4 ros2 bridge…
running make would not wrap Autopilot with ros2. to get all the topics of PX4 autopilot on ros2 you need micrortps agent and px4 ros2 bridge. look here
as for the sensor, migrate your design as per these guidelines. use the correct plugins for ros2. if you have already installed them then they can be found at /opt/ros/(distro)/lib
you can ofcourse work directly with the gazebo plugins and setting up the simulation environment first, or you can do the px4 ros2 bridge first. but to have the complete simulation environment for ros2 both will be needed.
hope this helps.