Which is the best introductory work about his philosophy? Reading

Are you new to philosophy in general, or just Nietzsche?

I started with the Gay Science

Zarathustra is probably the worst to start with

>>9144396
Just Nietzsche

>>9144392
start with Beyond Good and Evil, it was written specifically for this purpose

BGaE is what I started with.

Karl Lowith's From Hegel to Nietzsche. Hands down.

>>9144392
Well it is not Thus Spoke Zarathustra. If you only read one book then go for the Genealogy of Morals, which is probably the easiest book and a good place to start. If you know you want to read more than one book i'd start with Beyond Good and Evil and then go for Genealogy after.

Really, understanding most classical works of philosophy is very hard and if you have little experience reading them then it is normal to struggle. Having to read passages multiple times is almost a given. Using additional sources to help you understand the particular book can be a good idea, to help you know where the philosopher is coming from.