That is a boiler drain not a hose bib
it is soldered onto the pipe, it is not threaded
the way that you loosen that nut
using a 14'' or a 18'' pipe wrench
hold backup on the valve, so that it does not move
use a box end wrench, preferably a 16 point box end
turn the box end wrench to the left
View attachment 21881
many valves , the pipe fits into the brass
so you have an option. solder it or screw it
they soldered it
Thank you....you mentioned that it was soldered, if that’s the case how do I remove? Is it possible that there is a washer inside that could be replaced?