your questions makes zero sense
enter
Alt and Ctrl key are special keys. Then can be used as quick menu button or can be used to execute a program. You can also use them to do a shortcut key command.
the command is not available it is used in windows.its means at time execute command
system
apachectl start
There is no traditional 'execute' command in Unix.
You can right-click on an appropriate object to select a command, then right-click to execute the command. You can click on an icon to execute some commands.
A combination of keys pressed at the same time is often referred to as a "keyboard shortcut" or "key combination." These shortcuts are used to execute specific commands or functions quickly, enhancing productivity and efficiency. Common examples include Ctrl+C for copy and Ctrl+V for paste on Windows, as well as Command+C and Command+V on macOS.
that is the command for system file checker.
It will depend on the software being used but is often the Command and R keys.
Command prompt/line is used to execute entered commands. Command prompt is mostly commonly used to execute batch files, perform advanced administrative functions, and troubleshoot and solve certain kinds of windows issues.
To execute the main method of a class named smallprog using the JDK, you would use the java command in the terminal or command prompt. The command would be: java smallprog. Ensure that the class is compiled and available in the classpath before executing this command.