Unable to find (a)'On Hold Days' and (b)'Openings left to fill'

I am trying to look for the fields (a)'On Hold Days' and (b)'Openings left to fill' but unable to find them. When I say On Hold days, I mean the field should return the value for the days for which the requisition has been on Hold. And for Openings left to fill, the value returned should be the number of openings which have not been filled out of total openings. For example, if we have total 10 openings out of which 3 have been filled. In this case, the value returned by field should be 7. I have found field