How to use VR glasses to control the first person character's rotation?

I’m trying to make a fps shooting game in VR mode right now, I want to control my character’s rotation with my VR glasses. I’m already connected with steam VR, and when I start the game in VR, my vision is seperated with my character, a little lower than the eye level, not in the same direction when spawned,can not control the rotation of the character. I would appreciate if anyone can tell me how to make the right setting, I’m totally new in VR~