How To for Box Truck Tires

I just got this box truck as a project (yes I know the tires are shot) but I am scratching my head on how to even maintain these tires… 1992 E350 w/ 12ft box.

1. These rims have two tires on them.

2. The outer inflation nozzle doesn’t seem to have a valve stem in it, just a little pushy thing with a hole in the middle.

3. How do I even get an inflator to the inner valve?

TIA