Analyst444's post in Can you copy Notes? was marked as the answer
Here's what I think is the easiest way:
Open the Note you want to copy. - - - In the lower right hand corner on an iPhone (upper right hand corner on an iPad) are 3 dots. Click on them. - - - A menu of options will pop up. Click on "Duplicate". - - - A copy of the Note will be created and it becomes the "active" Note. Assign the Note is to your desired Notebook.