Q: How long should a driver focus on the turn-in point before looking into the corner for the apex?

Q: “How long do I tell my driver (6-year-old son) to keep his eyes on his entry point/turn-in spot before he picks up his apex? He finds his entry/turn-in spot off the exit of the previous corner really well, but then I feel he’s looking to his apex too soon and he drifts off his turn-in point, making his entry a half a kart more shallow then it needs to be.”