A lot of the older gas pumps had the sight glass reservoir. Mom would have to pump the amount into the reservoir and then drain it into the car's fuel tank.
It looks like the little kid might be climbing in on a side mount spare tire.
I think they could be optioned with one or both sides at extra cost. Side mounts weren't standard equipment. The rear mount was most common but they only came with one wheel as standard. The tire was extra.
The kid could be standing on about anything but he's too short to stand that high with nothing. It's kind of hard to tell if the car is a coupe or a roadster. It might even be a cabriotet.