Everyone can benefit from joining a group, even at the very earliest levels. The first Public Quest (PQ) in each zone is typically open for players of level 2-5 and gives great rewards by way of experience, influence, and items. You can only complete a PQ with a group. The easiest way to find a group is to click on the Open Party icon, located underneath your character portrait. If there is an Open Party in the area, or multiple open parties, you may join one of them without having to request an invite by clicking Join at the bottom of the frame. As a Bright Wizard, your role in a group is to inflict a steady amount of damage to the monster or monsters you are fighting.
A good group will consist of a minimum of one of each of the following: a Tank, a Healer, and a DPS class. The tank's job is to make sure that the monster or monsters that your group is fighting are always attacking him, and him only. Tanks are equipped with abilities and gear that help them mitigate a lot more damage than other archetypes. The Healer's job, of course, is to make sure that the tank doesn't die. He has a lot of armor, but he can't live forever. As a DPS class, don't expect to receive much healing if you get into trouble - your life is second to the Tank's. Your only job, besides staying alive and out of trouble, is to deal a steady stream of damage to the monsters you are fighting. However, you have to make sure that you do not deal too much damage too quickly. If you generate too much "threat" in the monsters eyes, he'll leave the tank and come straight after you - and then you're on your own.