Many wilderness survival techniques might be illegal in various places. There is no easy way to put this. You must consider the approach that you will take for your long term wilderness adventure. Depending on the reasons why you will be in the wilderness and if your experience is being video recorded (or photographed) or not, you must decide which techniques you will use before you go.
Pas vu pas pris
I’ve noticed that people doing long term wilderness survival stints either disregard unenforceable laws, or abide by them.This is an important decision that will impact your survival strategy completely! You must fully understand what are the local food resources available and if or how you will access them before you choose a location and make this choice. In French there is an expression: Pas vu pas pris. It means: not seen, not caught.
You must pay close attention to check if there are any restrictions or regulations for collecting wild edibles, hunting, fishing and trapping. Check which species are endangered, which animals have few or no hunting restrictions, and check the seasons and other requirements to comply with regulations. Follow all the rules that apply to you.
The best areas for long term wilderness survival should be isolated anyway.