Pls ! explain frame of reference. how is it different when you are riding inside a car or standing by the highway?

So when you are riding in a car everything you see is from the cars frame. Where if you are standing by the highway it is from your point of view.

Explanation:

So lets say someone sees a apple core outside the bus it looks like the apple is traveling the opposite way of the bus but to the man standing by the highway would say it is stationary.