I have 2 hens that are of laying age. I'm wondering if the laying feed for hens will harm my younger birds at all. It would be tough to feed 2 types of food.
Yes, it can harm them, or worse; the extra calcium in layer is rough on chicks and can cause organ damage or failure. But fortunately the solution is simple. Feed all of them chick starter, which is fine for adults, at least for a few months. Even medicated chick starter is fine, and you can eat the eggs, because the amprolium stays in the chickens' gut and very little if any gets into the eggs. You can also feed a grower, flock raiser or game bird feed -- most anything but layer. If you put out some oyster shell in a separate dish for the hens who need the calcium boost, you'll no doubt find the chicks don't bother it.
The younger ones should not get layer. You can feed your layers unmedicated chick starter or grower (or Flock Raiser) along with everyone else, and offer oyster shells on the side. If you have some layer to use up I'd mix it in sparingly to get rid of it.
Just leave them all on grower feed but add a dish of oyster shell to the coop. The young ones will try it at first but they won't mess with it much after that. Your layers will eat it as they need to boost their calcium. Problem solved!