Questions about Newton's third law

[thiotimoline]

I'm not questioning his law or anything, I just need to understand a few things about it. I understand the basic concept of the law, for every force, there is an equal force in the oppostite direction.

But what provides the reaction force in the following situations?

A car driving, has an applied force forward, but what's the reaction force backwards? Also, in the same situation, what about friction? It applies a force backward, so what's the reaction force forward provided here?

Second, a person lifting weights, they apply a force upwards to lift the weight, what is the reaction force here provided by?

A car driving, has an applied force forward, but what's the reaction force backwards? Also, in the same situation, what about friction? It applies a force backward, so what's the reaction force forward provided here?

The reaction force is just the air resistance by air acting on the surface area of the moving car in the opposite direction to that of the car's motion as well as ground friction acting on the car's wheel, also in the opposite direction to that of the car's motion.

Second, a person lifting weights, they apply a force upwards to lift the weight, what is the reaction force here provided by?

Your hand is doing work by lifting the weights upwards. Since weight of the weights is acting downwards, the reaction force comes from your hand's upward movement when lifting the weights.