You should not tile over wallpaper glossy surfaces lead paint or plywood.
How to install tile on plaster walls.
Wall preparation is an important step when you in install tile on a painted wall.
You may tile over existing tile painted or unpainted drywall plaster and textured walls.
Oil based paints can create a problem with tile installation consider removing this paint with paint remover or via sanding the paint away prior to installing the tile.
This surface provides the right base for laying ceramic porcelain or other types of tile.
However tiling over tile can add quite a bit of thickness so make sure your wall can handle the weight.
Plaster walls became popular due to the durability and strength of the surface and are more common in historic homes that drywall.