According to wikipedia, whose descriptions are good enough for iNaturalist, the plant in question is edible in all parts above ground
https://en.wikipedia.org/wiki/Anthriscus_sylvestris but some sources say it may be mildly toxic.
The confusion may arise from the fact that it is difficult to distinguish from hemlock, which is toxic.
Edited to add: all this refers to human consumption of course. I have found it extremely difficult to get any sensible nutritional information on wild plants, so would demand sources and evidence from anyone claiming anything about cow parsley as forage. (And for the sake of clarity, google does not equal either evidence or source.)