Choosing your "Main Class" Is it worth?

[Enkidoh]

Welcome to Eorzea!

Yes, you can change your class, but only when you get to level 10 in the class you started the game as. Once you've reached that point, you then have to do the quests for the Guild of that class up to the level 10 one to unlock the Armoury System (the game function that allows you to change class). Then you have to visit each class's Guild in turn to unlock each class. Once you've done this, each class you unlock you're given that class's weapon or tool. You then simply equip that weapon or tool to change instantly at will.

Arcanist (ACN) is a pretty good class to start as, as you get a pet (Carbuncle) to help you fight, you get a healing spell to heal yourself or a party member when you get to that point in the game (Physick), and later in the game, unlike other classes, you can actually unlock two Jobs for it (Summoner and Scholar). So it's a very good class to start as.

Unfortunately starting as Arcanist you're locked to Limsa Lominsa until you reach a certain point in the story, where you get your airship pass and can visit the other cities and unlock the classes for them. Until that point, you'll only be able to learn Marauder (MRD) which is a tank type class that uses a great axe, Armourer (ARM), a crafting class that makes armour, Blacksmith (BSM), another crafting class that makes metal weapons and tools, Culinarian (CUL), that are cooks who make various types of meals and drinks that you can use to temporarily boost your stats, and Fisher (FSH), a harvesting class that can catch fish and sea life for Culinarians to cook.

The other classes are found in the other cities.