I have two existing layers "Regards" and "Emergences", currently being written and possibly updated which I wish to feed with a common survey123 connect form, how can I do this. I created my form from one of the 2 layers but I don't know how to "write" the form so that certain questions feed directly into the second layer.
Automation software such as Power Automate can create and modify data in a separate layer. That would be your best bet for linking them.