How do you do ceramic backsplash?Do i need to prepare the walls first before puting the glue on?

I've seen it done on regular drywall no problem. In fact, they now make a specific glue for glueing tiles to drywall. I would personally clean the wall to be covered and take a scotch pad to rough up the Semi-Gloss paint, so the glue adheres better. It won't pull the paper from the drywall off because it isn't heavy enough, and plus it is partially being supported by the countertop. As stated, just make sure you caulk it up good when your done.