D/D PvE Dungeon Build (Need help)
Healing in dungeons is significantly less useful than doing more damage. The best “support” you can provide is 20+ stacks of might that you can put out with a scepter + Lightning Hammer build. The stickies at the top of the page will tell you how to run these sorts of builds.
If you really want a d/d or d/f healing build, the “classic auramancer” from here: https://forum-en.gw2archive.eu/forum/professions/elementalist/Neko-s-Comp-Guide-to-the-Dungeon-Ele/first is probably your best bet. But again, it is not good for dungeons, and more DPS would be a much more effective contribution to your team.