Learn to become as independent as possible, or at least be able to be independent if needed. Don't have to depend on anyone or anything except yourself and God. Be able to adapt quickly to your environment.
The most essential techniques that an individual needs to survive are the life skills. Life skills are behavioral aspects that help solve social issues in an individual's life. They go a long way in helping in survival because they utilize self confidence and strength to carry on.
I believe you should be able to find a clean water source, or at least something to drink until water could be found. Food is another concern; You need to know how to forage for food, hopefully you can find some that isn't too toxic to eat ( either naturally or man made toxicity.) Next you will need shelter of some kind, you'll need to know how to build a structure(s), if need be Or how to tell if a cave is safe to live in. Knowing animal tracks is important so you can tell which ones belong to predatory animals so you can keep yourself safe from them. You will also need to know their behaviors for the same reason, i.e. some bears climb trees, some do not, some big cats climb trees, most do not, etc.
if you want to wear clothing you have to know what will work best for that purpose and how to acquire the necessary materials. Being a good communicator is essential in case you come across other people that don't speak the same language as you do. Another useful skill for survival is how to care for yourself and other people/animals medically in case of injury or illness. Know how to tell which direction you are traveling anytime day or night.