Learn Polish: Warto dużo czytać. - It is worth reading a lot.

The word warto stands alone as an impersonal expression meaning "it is worth" or "it pays off." Polish doesn't use a separate word for "it" in sentences like this.

Why doesn't warto have a normal verb ending?

Warto isn't actually a regular verb; it's an unchangeable word used to state an opinion or fact. You don't need to conjugate it (change its endings) for "I," "you," or "he/she" — it always stays exactly the same.

Why is the verb czytać (to read) in its dictionary form?

After impersonal words like warto (it is worth), trzeba (it is necessary), or można (it is possible), the main action verb is always in the infinitive (the dictionary form). So, you just plug in czytać without changing it.

Could I change the word order and say "Warto czytać dużo"?

Yes, you can! Polish word order is quite flexible. "Warto czytać dużo" is perfectly correct, though putting the adverb dużo (a lot) before the verb, as in Warto dużo czytać, sounds very natural to native speakers.