need help really new

You should really provide more info / being more specific lol

Its like someone entering in a restaurant and saying"Im hungry,feed me QQ"

It all depends on your class, and your level according to the mob you're trying to kill. It's like, if you happen to be level 10 and the mob you're facing is level 55 = insta death lol. So make sure mobs you're killing are in your level range (their name will show deep green if 8 levels below yours, light green if 2-5 levels below, white if they are same level as you are, light orange if 2-5 levels higher, and finally deep orange if 8 levels above you, or if they are ? level mobs, which are generally world bosses and certain instance bosses) and also that you have a weapon that goes accordingly with your class. Magic classes wield glaives, patakas, magic swords, staffs, and in the case of psychics, soulspheres. Physical classes in the other hand wield swords, dual swords, pole axes, dual axes, pikes, fists, claws, crossbows, slingshots, bows (last three are archer only), and daggers (assassin only). So make sure you have an appropriate weapon and that mobs you're facing are white named or green named to make it easier; all you have to do is double-click the mob to whack it or click it once and then cast a skill if you're a magic user.