It's almost 100% stars.
In good conditions, you can see perhaps 2000 stars. (There are about 6000 naked-eye visible stars; of these, 3000 are above the horizon at any time, and about 1000 are hidden because they're too close to the horizon and blocked by the atmosphere.)
The number of non-star objects you can see without assistance is tiny in comparison:
- The Sun (obviously not at night, and of course it's a star)
- The Moon
- The International Space Station, but only a tiny fraction of the time
- The visible planets: Mercury, Venus, Mars, Jupiter, Saturn (and maybe Uranus if you have excellent conditions and better eyes than mine)
A handful of other artificial satellites might be visible, but only rarely. Comets can be very visible, but again that's rare. Visible asteroids are even rarer. Vesta, a large asteroid, may be barely visible, but I've never seen it.
Note that some of these objects are quite obviously not distant stars just based on their appearance.
Some galaxies (Andromeda, and the two Magellanic Clouds if you're far enough south) are visible, but they don't look like stars. A few of the brighter nebulas and globular clusters might be visible; the latter are groupings of stars, so I don't know how they'd count.
Meteors and aircraft can be visible, but they're within the atmosphere, and probably not covered by your question.