I just finished creating a separate interface for my IOT and guest devices and I'm wondering how I can make those interfaces support IPv6 so my parent's computers can communicate to the printers. I noticed that I can ping to the IOT device's ip addresses but can't ping to their hostnames. Is it possible to make my interfaces support IPv6 addresses?
Yes.
Without more information (i.e. your current IPv6 setup on the original network, are they public or ULA, the subnet size, etc.), there's not much more to offer.
Enough information to help (e.g. what was the resolved IP that it pinged, did it resolve, was this IPv4 or IPv6, etc.) isn't provided.
I also dont understand yet why you must use IPv6 for this task (i.e. you never explain why IPv6 must be used for your folks to access the printers).