One of the best examples is in Bill & Ted’s Excellent Adventure, when Ted saves the day by merely thinking about going back in time to steal his father’s keys to the police station.
Right after having that thought, Ted checks by the station’s sign, and sure enough, the keys that were missing in Act 1 were hidden in the future.
Much like Harry Potter and the Prisoner of Azkaban, we don’t see history change so much as we see it from two different streams of perception.
Everything that happens in the timeline is a fait accompli, and all we’re seeing is how things ended up shaping up to encompass the outcomes present.