I cannot find any documentation in common files folder of creo. kindly suggest from where to download vb toolkit\documentation.
Go to Solution.
You'll need to make sure that you installed the APIs when you installed Creo. There are checkboxes under "Customize Applications" when you go through the steps to install.
Make note of "where" you are installing. The default is "C:\Program Files\PTC"
After that, the documentation will be in:
C:\Program Files\PTC\<CREO_VERSION>\Common Files\vbapi
NOTE: The path may slightly change depending on what version of Creo you are running.
Hope this helps!