I m trying to find a name of a wall decor that resembles a glass cabochon but is bigger and usually has a an old fashion picture behind it?

No as most acrylic exterior paints these days are primerless . Read the instructions on the paint tin or just ask at the paint store they will tell you.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.