Kernel is the core of Linux system. In order to stay updated with the latest Kernel version, make sure you update your Fedora Linux regularly. But, in case you only need to check and update the Kernel only (not include other package updates).
To update the Kernel only, use the following command on Terminal as root:
yum update kernel*
When done, reboot your Fedora Linux and you will have the new and latest Kernel version installed on your system.