If there were really a massive nuclear war:
-- You probably wouldn't want to survive
-- You could survive the initial blasts by being far enough away from any of them (out in the middle of nowhere), or by being underground with some shielding (even in a standard basement is ok if you're away from windows, but farther underground is better)
-- You would most likely still be done in by radioactive fallout contaminating the water, food and air for many years to come. Even with expert survival skills, nuclear winter would drastically reduce the supply of every kind of food and what remained would be severely contaminated.