If you have zero knowledge about philosophy or you do not have a vast vocabulary. And still wanted to have a view on philosophy, "sophie’s world" by Jostien Gaarder, is the best philosophy book for absolute beginner.
It is also great for reader who like to have a wide view of topic rather than knowing details about the topic.
And it is best for curious people who just want to explore.

Spoilers:

Sophie the leading character of the novel, was liveing a normal live untill a mysterious letter reached her, and made her question her existence. It made her realise about how people have forgotten to ask questions.

The novel ends with leaving the reader with existential questions
And questions about reality.