If you own a Focusrite or Novation product you will get a product key for the Addictive Keys Studio Grand instrument. This product is an OEM license meaning that it can't be transferred or re-sold. You will only get one product key for your Focusrite/Novation account no matter how many products you have registered to it.
For Scarlett 3rd Gen, Clarett+, Clarett USB and Red interfaces purchased and registered on or after October 1st 2021, the Hitmaker Expansion is added to your Focusrite account for free which also contains a product key for the Addictive Drums 2 Studio Rock ADpak.
The product key(s) can be found in your Focusrite/Novation account, you can register product keys to your XLN account here:
https://www.xlnaudio.com/account/products/register
If you don't yet have an XLN account you can register one here:
https://www.xlnaudio.com/register
The product keys and licenses from Focusrite and Novation are only for these specific products and can't be changed to any other product licenses.