In relation to you asking about training specifics, the great thing about kids playing games, other than the players love it, is that it highlights the obvious areas where a Coach needs to work on in training.
So you mention that players back away when batting like they are scared of the ball, that's because they are scared of the ball! So the Junior Coach should be putting together drills to get the kids in that situation used to hitting a hard ball and facing a hard ball. It might involve drills over several sessions, first hitting straight drives off a cone, then drop feeds, then bobble feeds, then gentle throw downs, faster throw downs, then should be ready to face the slower bowlers in your group, then the faster bowlers. Then do a similar drill for pull shots.
All Juniors need exactly the same basic coaching, the difference is that some kids will instantaneous master a particular cricket skill, whereas some in the same group it could take weeks,months or even years.
Best thing to do is to offer to help out with the age group. If you go on a coaching course, you don't say what county you're in. But it will give you the background knowledge to devise appropriate training sessions.