In this trailer ceiling.. I am removing the light and putting a fan only in.

In the ceiling I have 1 set of black and white hooked together (in the cieling)..

Then coming out of the ceiling that is hooked to the light fixture is black to black and white to white...

Now my ceiling fan has a black blue and white...

How in the world do I hook this up.

FOr some reason up in that hole, they have some kind of metal wire screwed in as ground or soemthing.

Just attach your black to the bundled black and then white to white, secure with a wire nut tighten turned.

Is the box rated for a fan? In a trailer I doubt it.