It is true that having more people leads to the need for more food. Even so, overpopulation is not the major cause of food shortages around the world. In truth, there is more than enough food for everyone in the world. The real problem comes from the fact that it is not well distributed.
People in rich countries have more food than we need. We get fat even though we waste a great deal of food. Some people in poor countries do not have enough food. This is partly because their countries are not developed enough to have good agricultural techniques and technology. It is also partly because our economic system does not encourage an equal distribution of resources to all people.
As long as there is enough total food in the world for everyone, we cannot say that overpopulation causes some to go hungry.