Off Grid PV System Grounding Question
First off you should tell us where you are on the planet in order to get accurate answers.

1)There are 8 grounding points in the drawing. Which of them should be bond together?

All of them should be bonded so that they are at the same potential.

2) How many grounding rods I need? 

There should be a minimum of one ground rod per location and possibly two. If all this equipment is in the same location two should suffice. If it is spread out over a large piece of property then I would judiciously add more rods. There is no exact answer here. 

3) Where should I connect the Neutral Line to the Grounding Rod?

As close to the main service panel as possible.

Good luck!