Cannot draw in iPad Notes app using a finger
Found the solution!!! It’s in the settings. 
Toggle off “only draw with Apple Pencil” ... simple yet hidden solution. Hope this helps everyone :-)
You are correct that notes on iOS 13 does not want a finger to mark up on an iPad. It does work on the iPhone. Fingers are for navigation on the iPad build of Notes. I would recommend you draw in another app with your finger like Linea sketch.
- https://apps.apple.com/us/app/linea-sketch/id1094770251