Question: How can I see a video loaded in the background at any angle?
not only in the view of the camera or left right up down

Answer: 
Without using additional geometry or compositing, you can use the image as background for the world. Set the Texture coordinates to Window.

[![enter image description here](https://i.stack.imgur.com/blzHI.png)](https://i.stack.imgur.com/blzHI.png)
The question isn't very clear, but if you are looking to view your object at different angles, press down on your scroll wheel and you should be able to see at all different angles.