A Green Card holder who is not a minor can file Form N-400, Application for Naturalization, to obtain US citizenship. Similarly, he must have become a permanent resident before five years and must have remained as a permanent resident in America for at least five long years.
Now, flat paint is (usually) a latex paint that dries without a reflective finish-that's it-the finish is smoother (imho) than chalk paint. Chalk paint really dries quickly and it has a rough texture to it after it dries. Many people use wax or poly-acrylic sealant on top of their furniture piece to keep the paint from peeling. So there ya go, my best explanation.
The paint will appear at first no different than the basic latex paint you had before, but when the chalk paint dries on the furniture you will begin to see that faint, aged and chalky patina that you are looking for. You can double the recipe for a quart of paint, quadruple for a 1/2 gallon and so forth.