You can check the version of the Linux kernel that’s currently running on your Ubuntu system using the following command:
uname -r
The uname command provides information about the system and its environment, and the -r option specifically requests the release information, which is the version of the Linux kernel.
You can also use the lsb_release command to see the version of Ubuntu that’s running on your system:
lsb_release -a
This will display information about the Ubuntu release, including the release number and codename.