Dropped in the woods with nothing I can normally still get a fire going and get something to eat. However, planning makes the process a lot better.
I make firestarters from pine rosin and sawdust, and keep a few in the back of the Durango for trips. I also keep waterproof matches in there. Generally my wife and I camp together, so we'll even bring in wood in case the local wood is wet-you can always dry it by putting it around your fire, and then you have a source of dry wood to keep it going. Paraffin tea lights are also excellent for it-the paraffin coats and soaks into the wood, making it burn for 30-45 minutes.
Alone I keep flint and steel, waterproof matches and a lighter. But often I'm carrying a rifle or shotgun when camping like that, and if you are you can pull a cartridge, empty the thing and use the primer to get a fire going. Just don't dump the powder on it. Shotgun shells with paper or cloth wadding are the best for that. A 00 shell can be broken down into a firestarter, material for a signal fire (that powder I said not to blast,) a whistle (often the shot cup can make one) and enough ammo for a sling or slingshot to hopefully take one animal. Learned that on reservation.
Got tons more tricks, I might come back and post some more. The way I grew up made Ranger training look tame. I know my brother came out weighing the same as when he went in.