The Permanent Revolution & Results and Prospects
is an interesting read, but far from the jumping off point for a study of leftism. Results and Prospects
includes Trotsky's thoughts on the need for revolution that overthrows the monarchy and feudal system to push on until a dictatorship of the proletariat/working class and an international socialist system are fully realized. Otherwise, the revolution is incomplete and can become a reactionary counter-revolution. The Permanent Revolution
consists of a series of disagreements between Trotsky and Stalinists, with both parties playing the "I'm/we're closer to Lenin's ideas than you are" card. The book closes with Trotsky's summary of what he means by permanent revolution. As someone new to the topic, I wish I'd read these basic postulates first! Starting with the final chapter would have made the rest of the read less of a slog.
I suggest reading some foundational works by Marx and Lenin, and maybe even a history of the Russian revolutions, before tackling The Permanent Revolution & Results and Prospects
. The two works assume a basic level of knowledge about socialism, revolutionary philosophy, and figures like Radek and Kautsky. Not for beginners! But interesting nonetheless.