I am starting to play online poker. I hear everyone talking about poker bonus codes that give you free cash.

Poker bonus.Many poker sites offer huge sign up poker bonuses but i,m new to poker and i dont know where to play poker.Is it possible to get no deposit poker bonus?If yes-where?Best poker sign up bonus-50$ free no deposit.I dont belive in it.Is it possble to get poker no deposit bonus?Where?
Thx for answer