Propane Furnace Stopped Working, No Fan, No Heat

Should start by checking for 12 volts DC at the furnace. If 12 volts DC is present check for circuit breaker. Many furnaces have a circuit breaker to protect the motor. It is located on fan housing. About one inch square 1/2 inch thick with a red or white reset button.
No 12 volts DC could indicate a blown fuse in the 12 volt DC distribution panel.