#1
So i'm playing the guitar for my schools musical this year, but there are some chords I don't know.. I don't really know much theory so there are a lot of chords I don't really know. I tried googling them but I either couldn't find it, or there were like 34928903485234 versions of it and i didn't know which would be best..

I'm especially confused about these chords, i don't know what it means when one note is over top the other.

Gadd2/D
Cadd2/Bb

there are a lot more chords like this, but i don't list them all becuase i'm sure once someone tells me what it means i'll be able to figure out the rest


Aadd2
Bbadd2
Dadd2
Eadd2
Fadd2
Gadd2

AM9
Abm7
C#m7
Db7
DM9
D7
Ebmaj7
Eb7
G#m7
F#m7
Fm7

Bsus4
Csus2
Dbsus2
Ebsus2
F#7sus4
G7sus4
Gsus4
Asus4

E#dim

There are definitely a lot more chords than i realized. Even if you don't know or don't feel like giving me all of them i'd appreciate any help. Thanks!
#2
Gadd2/D and Cadd2/Bb are called slash chords. You play the first part of the chord, Gadd2, and then put a D note as the lowest note. A very common slash chord is D/F#. You play your normal D chord, but then fret the second fret of the low E string so F# is the lowest note rather than D.

As for the other ones, you can learn the theory behind them by clicking the theory link in my sig or by searching this forum; someone might be nice enough to explain the theory to you, but I am not (sorry). However, you could get away with just picking a few of those fingerings from Google and seeing which sound the best and are easiest to switch between.