Particles tab is not available when I use nurbs path New to blender and particles tab keeps disappearing from the right side panel. Not sure how to get it back or why it is happening in the first place.  I tried reopening document but it's still missing but if I open a completely new file it is there.
You need to have a mesh object as the emitting object selected. 

Currently you have a curve selected, and curves can't have a particle system.

Select a mesh object as the emitter, or convert your curve to a mesh (AltC)