It's not possible at all to do this for white-tailed deer. The does and fawns don't grow antlers. My state, NJ, has a population of over 100,000 deer and average densities over 100 individuals per square mile (with some areas over double that).
Indeed. You might as well try to paint all the squirrels or pigeons.
You could snare the does and put high-vis reflective vests on them.