The Basics
Water
That all life depends on water for survival; that clean fresh water is in limited supply; that water is sacred seems like it ought to go without saying - yet, we all take it so for granted. Stepping outside the convenience of water that flows from a tap brings a whole lot of perspective to this life-giving nectar. Effective planning is critical to self reliance. Next to air, water is the second most important nutrient for human survival.
Heat
If you have the opportunity to pitch a tent on one of the beaches of the world and build your life in year-round sunshine, staying warm is not an issue. On the other hand if you're any kind of familiar with damp cold whistling through your home during a January snowstorm, the NEED for heat is obvious. A heating system that supports a self-reliant lifestyle takes planning, but it can still be simple. Low technology example: is a wood stove; high technology example: is an ambient heat gathering system that keeps your home warm with no effort on your part and 'burns' no fuel.
Energy
Our personal comforts are largely tied to our capability to produce electricity. Self reliance means that you become your own mini-power company. There are now many 'off-the-shelf' options so that you never need to be in the dark again. In today's world, decentralization is becoming the norm. A power grid made of independent power producers is far more flexible than depending on one centralized power source.
Food
Food can easily be stored against times of lack, but the habits of storing and rotating the stored food must be in place before the need arises. It is also good to know how to grow your own food. Start with simple basics: have a mini-garden on a windowsill and to store non-hybrid seeds.