That is impossible to answer because scientist don't know ALL the galaxies.
About 13.1 billion light-years
Mainly that galaxies that are very far away (i.e., from the distant past) look different to galaxies that are near-by (from the more recent past).
As far as we know, most, if not all galaxies have a massive black hole at their centre.
They can be. Something that is far away is distant. but in "How far did you come", you could not substitute distant.
For example, galaxies are very large, very massive, very bright, and (most of them) very far away from us.
No. Distant is an adjective meaning far-away.
quintillions of miles away.
It doesn't. The Doppler shift can tell you how fast something is moving towards us or away from us; not how far it is. Only in the case of distant galaxies can this be used to estimate the galaxy's distance, because of the expansion of the Universe (galaxies that move away from us faster are generally farther away).
This question is formatted improperly and does not make any grammatical sense from what I can tell.
Galaxies do exert significant gravitational attraction on other galaxies. For example, the Greater and the Lesser Magellanic Clouds are galaxies that orbit our own galaxy, the Milky Way. In that sense, the stars in one galaxy do have a gravitational interaction with those in other galaxies. Of course, the more distant galaxies have correspondingly less gravitational interaction with ours.
Far away
one that is far away
Most galaxies have a red shift away from us - meaning they are moving away from us. However, the Andromeda galaxy has a blue shift, which means it is moving towards us. In about 2.5 billion years time, the two galaxies will merge.