All of Africa is not starving, sure, but hopefully you can understand how people can reasonably believe that there are issues with food supplies in much of Africa[1][2], and that a large number of people are suffering as a consequence. It is a tagline that has been thrown about in the Western world for decades and can be remedied with counterpoints - I was frankly having trouble finding any good stats re food supply in Africa.

[1] https://www.nytimes.com/2017/03/27/world/africa/famine-somal...

[2] http://mgafrica.com/article/2016-02-12-africa-food-crisis-20...