Here is the thing you might be new to mmo’s and possibly more video gaming in general i am not sure since it was not specified, There are jobs that many players do in any mmo. What class you decide on should be a personal choice because any class can do any job, some are simply better traited to serve a particular purpose is all. Try them all and do what you enjoy. Also the more you learn about your character and what they can do , the more fun it will be.