Game set and match in 1 hour and a half. Then many of us would prepare to die from the poisoning of the atmosphere, and recover to a degree in about 30-60 years, in the metorpolitian areas.
Individual survival would depend mostly on the blue zone or red zone status, geographically speaking. Much can be done to maximise the likelihood of survival and recovery in the event of a nuclear war. It's not as "end of the world as we know it" as we have been told it is. However, NOW would be a good time to review the preparations, and make them. It is doubtful the internet would be in place for you to log on an get the more critical issues settled AFTER an attack.
This entire book is online, apparently to read and print sections of as needed. Interesting. MANY will surive if such a scenario occurs. Except for those in rogue nations who are stupid enough to get something started.