Although I'm completely unqualified to command, I'll assume for the scenario I'm the captain on the first in rig.
On approach we would see the smoke and catch a plug on the way in. We establish command and stretch lines.
Step 1: size up - visual 360 of the incident. Confirm the dispatch details and the situation as described in the scenario.
Step 2: call for help - based on location, life safety, potential for escalation, I'd strike out another alarm. Order the second in crew to ensure the pumps are isolated and power is cut. Third in establishes a RIT sector.
Step 3: Rescue - Pull two 38mm lines, form a wide water curtain to push flames and vapors away, advance and pull out the child.
Step 4: Cover exposures: after you've pushed the flames around to facilitate the rescue, we may need to focus on new areas of fire spread. The involved car is now $50 of scrape metal but the building and other vehicles may still be saved.
Step 5: extinguishment: Pull a foam line and knock down the bulk of the fire.
Step 6: Overhaul: Confirm that all fire is out, release any unneeded rigs, take air quality readings, and throw down enough absorbent to soak up the fuel. Crank up some fans to disperse any remaining vapors. Gather the information for reports, terminate command and hand the scene over to the RP.