#1
Only been playing for 3 weeks so be gentle pls

Looking for some advice just to make sure i`m doing things right, for example

Barre chords... if i take D maj , move it up 2 frets and barre the 2nd fret does this become E maj ( as long as i only play the 4 strings )? and does this apply to any `open` chords, whether in minor etc providing i only play the right number of strings...

Also regarding power chords / 5th, the root note is always the note that the index finger is on?

Many thx
#2
yes and yes except on the E5 which is ur second finger on the second fret of the A string and the A5 which u move down one string
#3
On Barre chords- yes. If you take a standard barre chord like Dmaj (x5777x) and move it up 2 frets (x7999x) it is Emaj. But you can't do that with open chords, persee(shit I hope thats how you spell it ) A standard Gmaj (320033) will not become Amaj if you play it (430044) but it will if you play (431144) but I find that quite difficult .

Regarding Power Intervals (they're not chords because they aren't a triad) Yes the basic shape is index on root and ring or pinky on 5th like a standard G5(35xxxx) or (355xxx) where the ring places the octave as well.

Hope this helps you.