In areas where LAANC is available, use it. As far as the parks, you not only need to check airspace restrictions, but also any park rules regarding the use of drones.
For your specific question... see post #2.
But honestly, you should keep a cool head instead of just reverting to an automated flight mode if you lose track of your drone.
Just release the stick as a first step, then switch over to the DJI Fly...