The Secret World Leveling Guide
Unlike most other MMORPGs out there, The Secret World does not have levels. It follows a more indepth system that older games like Asheron's Call and Anarchy Online used. In this game the experience that you earn will go to other totals such as Ability Points (AP) and Skill Points (SP). These points are used to increase your effectiveness in combat and outside of combat with things such as quality of items you can equip.
Depending on how you spend your points you may or may not have a hard time with the game. There are recommended builds for players to follow or "decks" as they're called but there is still room to "gimp" yourself and be unable to fight toe-to-toe with harder monsters. For this reason you will want to take the game slow, do each quest once or twice and be sure to kill monsters while out doing quests.
For this reason there is no indepth leveling guide I can give you, yet anyway. For now most of the information I can provide you with will be on my "quests" page of my website. This will have tons of tips and secrets to help you get over the harder more annoying quests in the game.