What does Brian decide his shelter should provide in addition to keeping put the wind and rain?
The shelter is decided to become Brian's own sense of "home" when trapped in the wilderness setting. Brian utilizes the shelter as the domain that can actually be his in a setting where little else is. He senses that the shelter can represent a level of control in a setting where he has none. In keeping his shelter dry, he is also able to discover how to make fire with throwing the hatchet against its wall to scare away the porcupine. He does not "decide" this, but rather understands it as a function of the setting. The shelter, thus, helps to provide Brian some level of sanctuary and privacy in the wild, something which proves essential to maintain his sanity and sense of focus in overcoming the wild.