I literally "train" pullets. It is harder to re-train older hens, but this is what I do. I give them a laying box or two just, just before they begin laying. That time is coming when they get their red combs and wattles and some begin to squat at my feet. Only then do they get a laying box. I place a laying box or two right on the floor of their coop. I don't expect them to figure out a laying box that is up high until much later on, as mature hens.
If younger pullets are in with older hens, the older hens set the example and I don't have to do any teaching.
It does help to put a golf ball or two in the laying boxes. I've seen the pullets stare into those boxes at that golf ball with great interest. I'm sure they see it as an egg of some kind. I also will not let point of lay pullets range until they've mastered the egg laying in the box, which normally takes place before 2 pm. I'll range them from 2 pm to dark.
Once the training period has ended, then they are safer to let out at noon and then, eventually, at 10 am perhaps. Best wishes.