The free drone racing simulator released by DRL is one of the best free sims out there right now, hands down. While no sim gets the physics exactly right, the DRL Drone Racing Simulator (currently in beta) gets it close enough to get some practice.
They've included the actual locations from their first season, with multiple tracks for each - this video shows the HUGE outdoor map that surrounds the "Gates Of Hell" factory location. The full map has the factory, a shipyard, forest, a city, and even a cave system you can fully explore - at any time, flying seamlessly between them all!
If you've got a decent gaming rig and a gamepad, you can try drone racing right now - even better if you have a transmitter you can connect via USB!
https://thedroneracingleague.com/simulator/
