You can find the missing stl files on the printables page of my model: https://www.printables.com/model/98646-orchid-pot

A design I saw first on ALL YOUR TECH channel, but he never shared it anywhere even as a pay for model. I decided to make my own version.

You should be able to put the soil directly into this pot without any other method of containment, maybe some sort of garden fabric if your soil is particularly fine.