Elitist Jerks is a forum focused on end game raiding, and not really a place to find the starter information you are looking for. There are many sites and guides available on healing as a priest, and a Google search will uncover a wide selection. You might also want to look at the PlusHeal community. Their focus is much more general and will have discussions for those just starting out. Personally, I do think that healing dungeons as you level is a good way to learn to heal with a new class.
I look forward to seeing you back here with us as you gain experience and prepare to take on greater challenges.
I just rolled a BE priest speced in holy and he is currently at 10 should I level him in the dungeon only?