Leonardo da Vinci said, “I have been impressed with the urgency of doing. Knowing is not enough; we must apply. Being willing is not enough; we must do.” (see: https://www.youtube.com/watch?v=XqECLqBOkXM&feature=youtu.be )

What does that have to do with igniting a fire with no matches? Keep listening and we’ll see if we can make the connection.

What do you need to create a fire?

In answer to that question perhaps you with are thinking what your Jr High School Science Teacher said 

 “Fire is an elemental self-sustaining interaction between 3 required ingredients; Heat, Fuel, and Oxygen. These three are required in sufficient amounts for a fire to burn. Remove any one of these 3 and the fire goes out”.

That is one correct answer. I would propose however that you might need something else, something even more vital, to ensure you can start a fire. 

Experience.

There is a difference between knowing how something is done, and doing it.