'Raava' is a book about... well, Raava. Raava is one of the Saviors, a group of people chosen by God to protect the Earth. With them is Thomas, a boy who must be protected because he is said to be "the one who restores the balance in the world".

First, let me say that you can expect quite some constructive criticism; in my opinion, a lot of things could've been done a lot better.

Starting with the characters: I didn't care for them at all. I've spend the entire book trying to figure out why, and I still don't know if I did figure it out, but this is what I found: I didn’t notice character development. The characters don't change throughout the stories. They don't seem to evolve. This does get a bit better near the later chapters of the book, but still.

There's also that the characters seem to succeed in everything they try. I haven't seen Raava lose a fight even once. I don't recall seeing the other characters losing a fight either. Only Thomas did, but he's kind of weak and not a savior, and he did kill his opponent so I guess it was sort of a tie.

Grammar and punctuation could also use some work. Try to add commas in certain places, as well as editing out some spelling mistakes.

Lastly, I've taken some pieces of dialogue out of your book:

"Raava? What are you doing here? He asked.

"I mean thanks for saving my life and all but what are you doing here?" He added confused.

A lot of dialogue is written like that, and sometimes it's confusing and it breaks the flow of the story. Maybe try writing like this:

"Raava? What are you doing here?" he asked, confused. "I mean, thanks for saving my life and all, but what are you doing here?"

It sounds more natural like that (I've also added commas where necessary)

As for the plot, I do like the concept, but I think the book would be a lot better if you fix the issues mentioned above.