Mohamad said:
According to the Newton's third law "For every action, there is an equal and opposite reaction." When a car (or a bike) turns, How does the car (bike) exert force outward (in the opposite direction of centripetal friction force)?
You can consider the force (action) and the opposite only considering the whole system, car and earth. The two forces give zero sum for the whole system.
At steering Earth will counter rotate, (if perfectly rigid body), but i will not even try to measure how much.
In reality Earth will counter rotate for the force remaining at net of all dissipative effect ending in heat (deformation of tires, asphalt, road substrate, dow to geology deformation..) i think close to zero.
The main forcesarise from there mechanical effects, outside the car.
maybe a more clear situation is straight acceleration, a car star accelerating (big), the Earth accelerate (very little) in opposite direction, the two forces are equals and opposite, the difference is in the mass of the two objects of the system.
Centripetal acceleration from steering is the same.