It is estimated that at least 2/3 of the world's surface area has yet to be touched by human life. There is plenty of room for twice as many people as there is now. The only problem is politics. When the world was young, anyone could build a house for their family anywhere they wanted. Nowadays with civilization, every country takes count of people, and the resources shared within can run out.
The population problem has more impact when there is a government that supplies food, shelter, and safety to its occupants. Concentration of people on one area like a city, town, or village can also have an impact on the area. Where there are places untouched by humans with plenty of plant life for them to feed, which are unknown to them.
We live in a "cheapskate" run country. There is plenty of land in the United States of America to build homes for the homeless. Plenty of room to grow vegetables, nuts, fruits, etc. but doing so requires money which the government is not willing to spend. Before a government was built like I mentioned, anyone could built and plant wherever they wanted.
With the extreme costs of houses, energy resources and such it seems like the population is too overwhelming to accommodate some resources. Specially when people now need electricity, televisions, computers, etc. to live a normal life. None of those things were needed 200 years ago. Life has become extremely expensive. That doesn't mean that the world is over-populated.