I made under $500 in income last year, should I file my federal income tax

Believe it or not: IF you received a 1099 MISC for $400 or more then in theory, yes.

If you received wages with taxes taken out, it's to your benefit to get them back and see if you can get the Earned Income Credit, which might get you about $300 (and no, you don't have to have children).

But you don't have to file.

You had to have been supported by someone, gov't benefits, or a shelter or living program, right?