You can use nano an editor.
That’s a program.
Programs are started by just typing their name on the command line as the first word.
In this case you want not just to open the program but a specific file.
So you need to specify that as a second word.
All words/items beyond the program name are called arguments.
nano is the program name and -h is the first argument.
This will show you the help for nano.
Anyway if you use a filename as an argument it either needs to be the full path or a relative path.
The current directory should be shown at the start of the line (command prompt).
~ is a shorthand for your home directory also know
If a path starts with / it’s an absolute path, otherwise it’s a relative path.
If settings.php is in your current directory you can edit it like this:
ls you can check the contents of the current directory.
cd you can change the directory, for example:
take a look around with
probably there is a directory listed named flightairmap, settings.php is probably in there.
Anyway i asked you to edit
settings.php, a file, not THE settings
You’ll figure it out eventually, maybe find an introductory guide for the command line.