Per Einstein's space curving=Galaxies follow curvature or expand Universally in a radial direction?

Answer 1

I think that a galaxy is too small to be a reliable indication of the curvature of the universe. Galaxy revolve around each other, collide with each other, and generally move in all kinds of directions.

Astronomers look at clusters and super-clusters of galaxies to study the large-scale structure of the universe, and its expansion. A "group" of galaxies has (at most) a few dozen galaxies, and a "cluster" has from 50 to up to 1000 galaxies.

A super-cluster is made up of several clusters.

Answer 2

The direction of the expenditure and the curvature of space have nothing to do with each other. Galaxies move away from the presumed center of the universe radially in a straight line.
The curvature of the "Universe" means that the space where this straight line is projected is curved. This curvature would only be observeable from outside our 3D+1 (Time)-world.
Hard to grasp an idea but that is higher physics.

Answer 3

Both. As an analogy, if there is a crowd of people and they all scatter, do they spread out in a radial direction or do they follow the curve of the Earth's surface? The answer is both. Three dimensional space is curved in the 4th dimension in a way analogous to how the two dimensional surface of the Earth is curved in three dimensional space. But it is only an analogy, space is not the same as the surface of the Earth.