Sort of. A true pinhole camera creates an image that is already 100% focused. The bigger the hole (“aperture”), the wider range of angles the light is coming in at, and the blurrier it gets without additional focus. (It’s not “noise,” it’s the wrong signal.) Think of holding up a piece of paper, take a little square on it, and imagine where the light comes from that hits that square. If there is no pinhole at all, and it’s just open to the environment, the light that hits that square is coming from all directions and you just see white. If you block out all but a medium sized hole, the light can only come from the direction of the hole, but there are still several possibilities for its source which get mixed together in a blur. Once you shrink down to an infinitely tiny hole, the light hitting any spot on the paper can only come exactly from the direction of one point on the other side of the hole. Repeat for every other point on the paper, and it’s in focus and you get a picture.

The problem is that an infinitely small hole lets in no light. And the wider the hole, the more possible angles that light can come in at, and the blurrier it gets. That’s where lenses or refractive mirrors come in, but OP didn’t ask about that…