Force is a concept used in physics to describe the interaction between objects and the changes in their motion. In classical physics, forces are often associated with energy transfers, but it's important to distinguish between the source of a force and the energy associated with it.
Force can exist without a pre-existing energy source in the sense that it doesn't necessarily require an external energy supply to manifest. Forces can arise from various sources, including fundamental interactions such as gravity, electromagnetism, and nuclear forces. These forces are considered fundamental properties of the universe and do not require a distinct energy source to exist.
However, when a force causes a change in an object's motion or position, energy is often involved. Energy is a more general concept that encompasses various forms, such as kinetic energy, potential energy, and thermal energy. When a force acts on an object and causes it to move, energy is transferred to or from the object. For example, when you push a car, the force you exert transfers energy to the car, causing it to accelerate.
So, while forces themselves can exist without a separate energy source, the effects of forces often involve the transfer or transformation of energy.