2

You must navigate to your default install location for 3.6. For IDLE 32 bits it's:

C:\Users\\AppData\Local\Programs\Python\Python36-32\Scripts\
for IDLE 64 bits use:

C:\Users\\AppData\Local\Programs\Python\Python36\Scripts\
If you navigate to that directory in the command prompt (use cd command), then the command

pip install pyperclip
should work.