Is there any instance of a sphere in nature, as in any surface equidistant from a point?

The Earth and the Sun are both "oblate spheroids" - no large body can be perfectly regular.

When you look at quantum objects they do not HAVE a shape, they have a volume of probability. So the electron can never be a sphere.

No, if you require perfection there is not one sphere in the entire Universe because quantum fluctuations are everywhere.

It depends what degree of variation from perfection you will accept.

Earth, the Sun and other planets are very close to being spheres. Black Holes and Neutron Stars are almost exactly spheres to within perhaps the width of an atom or two.

electron is perfect sphere. and if earth and sun are not sphere what is your definition of sphere, because they both fit in current definition of shere including billiard ball