modes and their chords

my friend gave me a sheet with this on it:

ionian maj7
dorian m7
phrygian minor
lydian maj7
mixolydian dom7
aeolian minor
locrian m7b5

it has the modes on the left. on the right is the type of chord you should use when you are in a certain key. example if you are in C and you want a chord progression that will work with the modes of C you can only use any of the following chords(in any order and position depending on your chord progression):C Dm7 Em Fmaj7 Gdom7 Am and Bm7b5

what I am wondering is: first of all what is a dom7 chord? and how do you make one? what are the fingering patters for it?

after Ionian why does it say maj7 instead of just maj? isnt the ionian mode just the major scale?

is maj7 the same as saying just 7? eg is Cmaj7 the same chord as C7?

Yeah, the Ionian mode is just the major scale. The same as Aeolian being the minor scale we all know. It's just the names they were given.

C7 and Cmaj7 are definitely different chords. The Maj7 emphasises the root, third, fifth and seventh. Where as the C7 chord emphasises the root, third, fifth and flat seventh.

A dominant chord is always the fifth degree of the scale. The mixolydian has always been known as the dominant.

C - I   - Tonic

D - II  - Super Tonic

E - III - Mediant

F - IV  - Sub Dominant

G - V   - Dominant

A - VI  - Sub Mediant

B - VII - Leading Note 

The Leading note makes you want to continue on to playing the Tonic, because it leads you on and makes you feel as though it should end somewhere else, that's why it's called the leading note.

The notes for the Dominant Seventh chords are a normal root, third, fifth and seventh that you would play, but it's called the dominant because that's it's given name.

Hope that was helpful! :D

ok thanks for clearing that up for me

No problem

Additions should be made in the following modes
Dorian 6
Phrygian b2
Lydian #4
There are obviously some others, but these are the fun ones :)
For example try this
Gm7 Gsus4 13 Bbsus#4

Pretty much though the rule is, the chords only involve notes that are in the scale its being played in. Within these limmits the chords are free to add the notes freely.

i have a question, how chords are named? for example open E why is it an E?

That's just the way it is. It became the standard tuning for the guitar. Though you have many musicians who go away from this standard tuning, Andy McKee for example. But it's easier for beginners to have the same tuning. Otherwise transcribing would be insane.

Well it comes from the notes that make them up. But right now my advice to you would be to look at the bass note.
For example the open E chord starts with an E, so depending on the G or G# its minor or major E.

dont hold this as gospel though, it is not entirely true.
If you choose to dig deeper into the theory behind it, start from the ground up.
But right now i would stick to that aproach for you.

If you really want to learn about it I would always suggest a teacher over any online advice. Online advice is always fragmented since music is such a big concept, a teacher can propperly guide you through it all.
Only get knowledge form online resources after building a big enough wealth of knowledge to know whats right and wrong, and only for distinctive pieces of information.

is there one scale i could play over the three chords of a twelve bar blues progression?

Normally one would play the fitting pentatonic or the blues scale.

Because the pentatonic leaves out some notes, it is more free in its application compared to your standard major/minor scales.