It is from FAO data which is taken from Pakistan own official production metrics. It is just then divided by population and certain things are normalised another way (like say the overall average omega 3 per 100 gm of generic fish etc).
There are however arguments to be made when the classification is very general (with say fruit and veg....not every fruit and veg is the same nutritional equivalency....and sometimes some production of non-standard fruit and veg does not get collected by the FAO)
As for the death rate from hunger, that is from Pakistan's official stats as well (that it submits to such places like WHO).
For example:
http://apps.who.int/gho/data/view.main.ghe2002015-CH13?lang=en
Resources that use FAO, WHO (and other data):
https://foodsecurityindex.eiu.com/
https://www.globalhungerindex.org/results/
https://ophi.org.uk/multidimensional-poverty-index/