Alright since my brother wont be home for 3 days, i cant ask him for info

Ok so for level 15-20 will that take me awhile? 2-5 hours tops?

and if i pvp, im playing on rp-pvp can i still R.I.P people once i hit 20? In the area, like once i hit the new area i can start to pvp places? And does pvp give xp?
like good xP?

Honestly?
The fastest Ive gotten to level 20 was 3 hours.
You do your quests(ALL of them) after you've beaten the Boozer bullies in Rum and Rumble in Tortage City several dozen times(They respawn FAST as fuck and they dont agro, save for the two that are RIGHT next to each other)and then you finish your high xp quests, finish you destinty quest and then head to your homeland.
This isnt an exploit, it's just smart gaming.