"Hi pretty! i love you very much!!".
(love in this case can be considered as love for a friend, not necessary as love between two people of the opposite gender that may lead to a relationship, in that case it would have been "ciao bella! ti amo tanto!!".
Ti Voglio tanto bene "can be used to express deep caring for someone: friend, parent..for a partner you use "Ti amo tanto. so TVTB can also be translated : I really care for you
Ciao here is Bye, because, ti voglio bene is usually used at the end of a meeting or discussion."