Greetings and welcome!
I have to agree with the EggKooKoo and the link posted. Playing CoH is not like other MMO's.
If I could make my own recommendations it would be: Play the tutorial and read the dialogs. They will tell you about using your new-found powers, Inspirations (temp buffs/heals/wakies/etc), and slotting enhancements that boost individual powers.
Oh, and due to the pervasive buff/debuff abilities on many Support architypes, there's not much use for "healers". :) (Many of these classes have heals, but for most of the powersets they are outnumbered by their other available powers.)