The surface of the earth has about 126,041,600,000 acres on it.
Of this, about 36,806,400,000 acres are land, and...
... about 89,237,760,000 are water.
Lets give every person on earth 10 acres of land for his very own. This means that there is room for about 3,680,640,000 people on the land. That's over 3 and a half billion.
People are very ingenious. They can figure out many ways to make many levels for people to live on. We do this already. They are called highrise apartments. We can easily support multiples of the above 3.5+ billion.
In addition, there are such things as subterranean floors. We have these already. They are called basements. We can easily support many more multiples of what we have listed above already.
People are very ingenious. They are figuring out ways to live on the surface of the ocean -
https://www.seasteading.org/. Once this becomes completely perfected, we have room for countless billions more people to live on, above and below the surface of the oceans, while harvesting an abundance of ocean-grown food.
There won't be even a hint of population problem for 500 years or more into the future.
Current population problems are government greed problems.