2000 concorde rad problem

I was trying to do a temp fix to my rad,oil was leaking at the fitting(was cracked from age) and upon trying to remove the fitting the large nut behind has come off releasing coolant out of the oil line. Is the oil line just a regular flare fitting? Do i need a new rad now that the line just spins in the rad? How does the cooler work on the side of the rad? Could i have broken something inside?

Thanks in advance