Guild Wars 2

can you play cross realms ??? because im lvl 17 on both or you start on lvl 1 ?

Hi guys, i recently startet to play the game.. about 4 days ago.. and i really cant decide wich proffesion to go for… ive made a necro, a warr and a mesmer.. Necro i made because i thinking warlock, dots and dots, and new melee spec in exp.. warrior ive made because im loooooove melee bruiser.. but what i read on forums, warriors sounds pretty weak compared to other classes in dmg ??? and mesmer should be wild dmg dealer and avoider.. maybe some of you guys and give me some lvl 80 tips, who have easy to run instances or get spot, and strong in pvp.. ?

i like necro and warrior gameplay,.. but who to choose to lvl is were im lost

thx in advance guys, and hope to meet you all ingame