I keep hearing everyone talking about building more buildings,but where? Do you have to have a certain population to build more than the one hut and repair the other? I need more to build to make a master builder.

Some buildings are puzzles, and some are related to larger populations. It takes a little time to get to everything that can be built.

As your tech levels go up you get new things to build, also when your population goes up the foundations will show up.

The foundations will pop up at the right time, like they do with the huts you also need the right level of tech also you gain building skills for two other things besides buildings