A car accelerates on a horizontal road due to the force exerted by
Friction force applied by road on the car act in the direction of the motion which is responsible to move the car.
If a fly collides with the wind shield of a fast moving bus which experiences an impact force with a larger magnitude :
From Newton's third law of motion both bus and fly will experience equal force in opposite direction.
If action force is gravitational force, then reaction force :
Action and Reaction forces are of same nature.