What should be painted on the wall of latex paint to make it smooth and able to write without damaging the paint surface, just like a whiteboard, can it be scrubbed?

Hello, I am a decorator. I have this paint. I produce a dust-proof coating in the liquid wallpaper coating factory. When you open it, you see it is milky white. After diluting with water, you need to coat a layer of dry and clean latex paint on the wall. After drying, the walls are bright and smooth and can be painted. After painting, you can directly rinse with water. As long as you don't hit the wall with sharp and destructive things such as hammers and scissors, this layer of paint will hurt children.