the tuning of each string from the top down, is E A D G

you got it backwards. from the top down its g d a e. sorry im picky.

What do we have here?......the paradox of interpreting graphics, uh?
It`s a matter of semantics, I guess.
Anyway. What really matters is knowing that the thinnest string on the standard bass is "G". And the thickest is "E".
So in tablature looks like this:
G---------------------------(thin)
D---------------------------
A---------------------------
E---------------------------(thick)
The distance from one fret to the next is a Semi-tone or half step; therefore a Tone or Whole step is two frets appart.
You can use a pick or your fingers.
However, you get best results using your fingers, when playing a technique called "Pop & Slap". Which is pulling the string and then releasing it, so the string hits the fretboard, producing a metalic sound.
Slaping is using the fleshy part of your thumb to "slap the string"... rigth where the fretboard ends.(close to the pick-ups).
There is so much to learn, like, arpeggios, chords, scale patterns, and techniques used in guitar playing as well, such as: trills, tapping, harmonics,etc.
My advice to you is, get some books and videos, and talk to other bass players.
I wish you luck man. I played the bass for five years, and I loved it.