@AbyssalMonkey you must not have much experience with mobile games then, because most of those skip the seasonal planting explanation, but force you to watch as your buildings are erected, some of them even require you to supply different materials for each stage of development. Guy stuck in the hospital, with nothing to do but watch YouTube and play video games, could definitely learn the necessary skills to build that hut, add in the couple years of working in his pocket dimension, and his level of skill makes perfect sense.
Edit: by skip the seasonal explanation, I mean that they let you grow whatever you want, at any time. So you're not likely to learn what plants need what climate, or how long anything takes to grow, but you will learn that a basic hut can be built from mud, twigs, leaves, and scraped bark fibers.