yes

We don't need to create buttons on images? Just need to put on xml.

Put it in the XML file after you download it.

Like so:

https://developer.vuforia.com/resources/dev-guide/virtual-buttons

N

Because i created button with image. I uploaded to target manager. But i didn't get anything in xml file.

Ok. How to set virtual button on image. If i have image, and placed some button with name on image. Is it enough? 

Is it possbile to play video?

Probably.  It's software, so you can do anything you can figure out how to do.

What can i do?

Study the code for BP and VB and try to figure out how this can be done by understanding how it works.

where to change the code?

This is something you need to work out for yourself.

If you are having problems, maybe try Unity, because the native SDK is for more advanced developers.  

Failing this maybe try to find/hire someone that can help you.

N