Pharmazeutisch-kaufmännische Angestellte is a person that specializes in ordering for medicine and drugs for the pharmacy, inspecting the orders and organizing them on the shelves, ready for sale.
The PKA is responsible for the marketing and accounting, they also interact with the clients and advice on the correct medicine to buy. The ausbildung is also known as Pharmazeutisch-kaufmännische/r Assistent/in.
More info in the video below. Info on duration and how much you earn, here in an older post.