Hi,
The way to do is:
1. Uninstall Fusion 11.
2. Download the Fusion 11 Pro version from below link and install.
Download VMware Fusion | VMware
3. Purchase the upgrade key from VMware Store.
VMware Online Store
4. A further better would be to contact VMware support, they should help you with the process and should also let you know any kind of discount/offers you may get.
