my daughter has locked herself out of her phone. so before I factory reset her galaxy j3 luna. she's is hoping there's a way I could hook up the phone to a cpu and save her pics & other files?
If the phone is locked and you are not able to open it in any other way, (check the lockscreen, sometimes email is an option), then the device content is gone.
You could try this though:
Take a look into Google photos, sometimes they are backed up there, just search Google photos on your PC.
They could be in Google drive too.