I am having trouble mailing a file that I created in Linux. The teacher wanted the command to be typed like this:

mail username < /Absolute/Path/From/Above

but it keeps giving me an error message that the file or directory created doesn't exist.

I created a new directory inside another directory and then created a text file inside the new directory, but I have tried so many different ways and I keep getting the same error. What am I doing wrong?