Go to right hand HUD panel, to the last tab, should be an emergency fuel option, I believe. I think there's an eye watering cost.
If you're still in the basic sidewinder, consider self-destruct. You'll get a new ship (don't take insurance option) and keep your credits.
Beyond that, next time invest 309cr in a basic fuel scoop, fit to one of the bays of your ship, and you should never run out again. Just fly near to a star while in supercruise, hit the brakes once temperature gets above 90%, you'll take ship damage above 100%.