rm is short for "remove", and it means it. There is no bin to fish files out of afterwards: a removed file is gone. Read the name twice before you press Enter.

The file to delete is notes/old-list.txt. That name has a slash in it: it means "the file old-list.txt inside the notes folder". That is a path, and you can use one anywhere a filename is allowed.

This is the command to be slowest with. Everything else here can be undone by doing it again the other way round; rm cannot.