I am confused about the situation where an airport is located in class G airspace and at the same time located in class D airspace. As we can see the picture below Spadaro (1N2) is located inside the Francis S Gabreski (KFOK), am I right? If so, do I need to call tower before entering class D?
Strictly speaking class D airspace generally has a radius of 4 NM. If you take a look at the TAC chart or hop on your favorite flight app you will see the field actually sits just outside the airspace.
The sectional is likely drawn this way to allow for 49N and 1N2 to both be properly depicted.
Officially the airport is closed according to the current AF/D it appears to have been shut down in 2016, so it may be listed there simply for visual reference as the physical runway seems to still exist but traffic overlap is no longer an issue.