Is masturbation safe?

Yes: The alleged dangers are part of the mythology of people who want to control your mind for their own reasons. It's almost universal, as a teen you will have sexual thoughts; it's a way to keep pressure down, a safety valve, and to learn about your body before you get married. Maybe an adult in your family can give you good advice. Don't use a prop that you might choke on.

That depends on how: It is done. Infection control or injury from angular objects or excessive force may occur.

Masturbation: Yes. It is both common, healthy and safe. Masturbation is a common and natural part of the human experience. Every man you know has or does masturbate. There are no negative health consequences in general to this common sexual activity.