How to check the version of the operating system in Linux?

In a Linux system, you can use the following command to check the version of the operating system:

1. Show the details of the distribution system.
2. Show me the contents of the os-release file.
3. What is the output of the “uname -a” command?
4. Print the contents of the file located at /etc/issue.
5. Display the version of the operating system by using the command “cat /proc/version”.

The above command can be directly entered and executed in the terminal.