Expanding the UI allows you to see available content for all levels. You can do the same for 3rd, 4th, and 5th Job. Here, you can begin your Job Advancement. 30 you will have full access to the 'Maple Guide'. To find these maps open the World Map ('W' by default) and search for the monsters listed above.
Some notable training maps if you do not want to follow your storyline are: If you are on Victoria Island you can find the following gear for your class here: If you wish to buy your equipment, in the town that your character started in will have an NPC that sells Weapons and Equipment. If you are looking for equipment, monsters at your level will drop the equipment you are looking for. They will get you to level 30 and 2nd Job From these levels, follow your class' storyline.