Available with Spatial Analyst license.
To use Spatial Analyst, the extension must be properly enabled in your user account.
Enabling the Spatial Analyst extension
Once the software is installed, you need to enable the extension before you can work with it. ArcGIS Pro requires that an administrator of an organization assign software licenses and extensions. Once you have been assigned the ArcGIS Spatial Analyst extension, you gain access to the tools.
The extension should be listed as Licensed.
Having problems accessing the extension?
If the extension is not available, either review the appropriate section of the Administrator Library, or contact your system administrator.