Do electrons exist in shells or can they be found existing as an individual? I am just a high-school student trying to self study,please excuse me if the question sounds silly to you.
A simple question: Are electrons always found in orbits/shells of can they even exist by themselves?
Related question: In an electric current do electrons move from one atom to another or do they actually flow through the conductor like they show in the animations?
 A: This curly track is the footprint of a single electron, kicked off an atom of hydrogen in the bubble chamber( there is a magnetic field perpendicular to the picture, and the electron keeps hitting and ionising the hydrogen (the dots), losing energy):

so, yes single electrons exist. Also in cathode ray tubes, like the old TV screens, there are streams of electrons in vacuum hitting the screen so that images are created for us to see.

In an electric current do electrons move from one atom to another or do they actually flow through the conductor like they show in the animations?

It depends on the material which carries the current. In the example of the TV screen, the current is in vacuum  and composed of a stream of electrons.
In metals the outer electrons of the metal molecules are shared by the whole lattice, (the wire) and they move within a wire for a small average distance, repulsing the next electrons but  the current appears with the velocity of light, because it is a collective effect. 
