Next line / return with an Apple Pencil?

I understand that, however I'm not aware of a way to make a system function with the Pencil. Especially when you are restricted by the entry of the Signature line at that point. Searching the iPad User Guide, I cannot find anything about creating a carriage return with the Pencil. iPad User Guide - Apple Support

In what way? Are you writing in an app? When I use my Apple Pencil in a note taking app, I just move to the next line and the iPad seems to pick up that it is a new line if I use OCR to change the handwriting to text.

I would suggest providing feedback to Apple to let them know. That is the only way they are made aware of features that users need/desire. Go to Product Feedback - Apple