Dray, the first dungeon I did was xCOE and I was like What in the F, lol.
Much easier now that I know how to play them.
Also try using:
It really makes a difference. You can also go tankier with your build while you learn. (yeah, don't listen to people that say crap like GW2 dungeons are so ez you just kite and lol while spamming autoattack in full zerk gear)
Fractals are good but the Underground Facilities (dredge) is fkin hard for a new group. Volunteer to be a paperweight on one of the plates in the gear room haha.