Hi there,
僕 ぼく is common among young boys ( when they get to their teens, most start using 俺 おれ among friends and people they no closely )
I personally have not heard a girl using this pronoun. I think people would find it strange if you use it, unless they are close to you and they know of your tomboyish personality.
The safest way to talk about yourself is わたし 私
or the more feminine way of saying it, あたし