No, you are not required to deposit and use real money to enjoy poker online. Most poker rooms allow for real money and fun money play. There are tables dedicated for those wishing to play with real money and tables for those preferring to play simply for fun. The same applies to tournaments as well, but for fun money players, poker rooms will offer freeroll that allows you to win real money and for beginners, this is a good way to get accustomed to playing online and having the opportunity to build a bankroll without any upfront investment.