How do make a projectile that pushes its target when it hits?

I’m making a project on which there are large cannonballs that should push away the character and make it fall from a platform when hit. I made a character controller manually, via code (its not the Unity standard). However, when the cannonballs hits the character, the balls are sent flying away, no matter that both the character and the balls have rigid bodies, and that the balls have a mass of over 8000.

In the projectile object, when the collision happens, you can get a reference to the thing it hit. Apply a force or move the thing that was hit through this reference.

I as soon as cannonball hits the man(or the instant before) I would turn off my character controller and switch to a rigidbody, then Once the rigidbody was moving slowly turn it off and go to char controller