Anakin managed to defeat Dooku through a combination of his raw Force power and determination. He used his lightsaber skills and quick thinking to gain the upper hand.
As he spends more time as a Sith, he might start to feel a sense of emptiness. He realizes that the power he sought isn't fulfilling. He could then have a moment of self - reflection. Maybe he meets a character who challenges his beliefs, like a young Force - sensitive who still believes in the good in the galaxy. This makes him question his path and start to seek a way back from the dark side.
The novel of Revenge of the Sith is canon. It aligns with the established Star Wars canon framework and adds depth and detail to the events depicted in the movie of the same name.
The plot of Revenge of the Sith centers around the final stages of the Clone Wars and Anakin Skywalker's descent to the dark side. It's a complex and intense story with lots of action and drama.