What do I need to get started with a simple simulation as a beginner?

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I need to simulate a simple drone and be able to give commands in flight and also get the real time sensor data. I tried using gazebo9 with ros-melodic and then found hector_quadrotor. I tried using it and then a bunch of errors popped up. One of which was that gazebo/math is not found. I searched online and found that it has been deprecated since gazebo8.

Please suggest a way to get this to work or another setup that is working for you.