I just planted some fruit trees in my backyard. Assuming all goes well there will be more fruit in the future. I plan to eat some of that fruit and give some of it to my friends, family, and community. That means that absent any decline the amount of goods available has increased.

You can make houses out of mud and clay.

Some countries are turning garbage into fuel and using that fuel to power their homes and businesses.

The economy can always continue to grow. It doesn't always grow, but there's no real reason to expect that we are about to run out of everything.

The only thing that I'm concerned about us running low on is food. Localized food shortages are likely over the next couple of years and that can cause major instability which is not a pleasant experience historically speaking.