Why is WebP support not enabled in GD on my server's PHP configuration
If you are not seeing WebP support enabled when checking your local PHP Info page, the most likely explanation is that you are using the CentOS 6 or CloudLinux 6 operating system, which doesn't include support for these tools by default. If you are using CentOS 7 or CloudLinux 7, cPanel automatically includes WebP support when GD is installed.
Here are two screenshots that show the differences in a PHP Info page - while yours may have slightly different values or settings, they should be similar.
While it may be possible to manually alter the system packages to get this working, that would need to be handled by an admin experienced with PHP configurations and customizations, and the lack of the WebP tools doesn't indicate an issue with your server.