Take the battery out of your Ryobi cordless drill and set it aside or on the charger if it's low on power.
Put on a pair of gloves. Clamp a pair of vice grips tightly on the drill bit stuck in your Ryobi cordless drill.
Take a pair of pliers and clasp the teeth around the chuck at the end of your Ryobi cordless drill.
Grasp the pliers firmly with one hand and the vice grips with the other hand. Turn the chuck counterclockwise with the pliers. The bit should begin to come loose or even drop out of the end of your Ryobi cordless drill.
Insert the battery back into your Ryobi cordless drill and use as normal.