The Force is everywhere. It is in all things. Some learn its nature and gain mastery of life, thought and matter. Most do not; but even those who do not know the Force, even those who are skeptical of its existence, still possess it. Some dismiss the Force's workings as mere luck; others recognize it for what it is.
As a Jedi you accept the Force and are able to use it in your favor. However, there is a limited amount of Force that a person is safely able to channel through themself at a given time. The more experience you have, the more you will be able to handle.