If gravity is not a force how does it accelerate objects?

Gravity is not a force but a distortion of spacetime. Since all objects exist in space and time, everything is affected equally by the distortion. Observers watch this movement as if the objects were acting under a force. An observer falling under gravity does not experience the distortion, but experiences free fall, where no forces are acting on the body. So there is no real acceleration, it just appears that way because we exist in spacetime.